Ongoing Log Cabin Maintenance

Hello and welcome to what we hope will be a useful guide towards the ongoing maintenance of your log cabin,.. yes it may come as a surprise to some but just like a lot things in this world, log cabins do need to be given some attention every now and then to ensure they operate as intended.

As much as we would love to provide you with a completley self contained product that requires zero maintenance it simply isn’t possible with this sort of building.

Please expect to have to perform the odd bit of aftercare.

Firstly lets just have a brief recap on how our log cabins are made so we can all get in the right frame of mind, by now you may have already installed your log cabin which means you will of already read our comprehensive online Installation manual, Or perhaps you’re still in the planning phase.. Either way we would suggest viewing the above to gain more clarity and perspective on the whole project.

Before I started working here, When I thought about “log cabins” I would immediately cast my mind to the wooden buildings seen in films made from round tree logs sitting in a snowy forest somewhere nice and peaceful.

Yes Please

Who wouldn’t want to buy one of these right!.. although you may need to make some life adjustments or sell a kidney to stump up the funds for this sort of project.

Our Log cabins are made a little differently and we like to think more financially and garden friedly, they consist of flat solid wall logs in a range of different thicknesses, stacked ontop of one another which then interlock in the corners with Wind and Weather Proof Connections.

28mm – 70mm Log cabin logs

These wall logs will in most cases rest on what we call Foundation Beams to bring them up and off your base, These foundation beams as a minimum will be pressure treated for longevity.

Standard foundation beam being used in a build
Our basic foundation beams being used, protecting the first layer of wall logs

After the walls are up you then turn your attention to the roof, These come in different styles and sizes of course but the principle around them is the same. You start with the purlins/rafters then the roof boards are fitted ontop to create the solid wooden surface to fix your roof covering to.

The roof being assembled on our Lauren 70mm Log cabin

Then low and behold!.. you have yourself a whole new building ready to be used for whatever you can imagine. looking for Inspiration?

A completed Lauren Log cabin

Easy Right… for some more information about fitting out buildings please also visit our Fitting Tips page.

So there we have it, thats the building up and ready to use but how do you keep it looking and performing as it should and what other considerations should you be thinking about to keep it a fully functional, problem free living space.

Perhaps the best way to go through some of the key points will be to break the cabin down into six areas .

  • The Base for the cabin
  • The Foundation beams
  • The Walls of the cabin
  • The Doors and windows
  • The Roof
  • Additional hardware and extras

Bases

The base is the first thing that gets laid and is critical for both the longevity of your building and its actual construction, i’m not here to talk about what base you should or shouldn’t use as all these details can be found with in our Base Support page already and in reality theres very little you should ever need to do to maintain it which is lucky as it becomes very inaccessible with a lump of a log cabin sitting on top.

However something to look out for would be subsidence, Let’s say you have a concrete slab, or a compact base with slabs ontop.. with the weight of the cabin ontop has it sunk it some places?.. hopefully not but its worth keeping that in mind to check if you find yourself with a misbehaving building.

Or perhaps you have built the cabin ontop of a raised Timber Platform and under the weight of the building one or more of the corners have sunk throwing out the top level like this unlucky customers did.

See the gap?.. Customers timber base had sunk in the middle

Luckily for this customer the timber base was fairly accessible from underneath so he was able to add additional support to bring it back level

Another important aspect of a base is damp proofing, using a Damp Proof Course ( DPC for short ) or a Damp Proof Membrane ( DPM ).

A DPC is generally used underneath your foundation beams, its purpose is to protect the underside of your foundations from rising moisture seeping up through your base as well as providing protection against ingress from the outside.

There are other ways to achieve the same level of protection, My favorite is to use a TAR product, painted on both the underside of the foundation beams and ontop of the base that they sit on.. applying this thickly will also service in sealing the perimeter helping prevent ingress.

A DPM is used underneath the concrete slab or ontop of it, This will again protect the underside of the cabin/floor from moisture that tries to rise up from and through your base into the building.

Advice on using a Damp proof course in your base.
Ideas for Damp proofing

Preventing this moisture from rising up within the building is very important, it can cause unwanted growth with in the building as well as other Unwanted Issues.

garden-furniture-mold
Nasty right!

Ventilation does play a big part in preventing this as well which we will cover in a moment but if you notice that a once dry and mold free cabin starts to experience these types of problems then a review of your damp proofing may just be in order.

Foundation Beams

Now these are also very important and often in truth the cause of great confusion at first with our more traditional shed building customers.

So just qucikly, Unlike a shed where you would expect to see a row of bearers all running the same direction with a floor built directly ontop..

A normal Shed is built on top of a floor with joists underneath it
A typical shed with bearers running the same way

The Foundation Beams servce a different purpose for this type of building. they only span under the perimeter of the cabin (as well as any internal walls that might be featured).. What they DO NOT do is span in the middle where the floor goes later on.

Their purpose is to raise the first logs off and away from the base which in turn protects them and provides added room in the middle for a floating floor

We have different types of foundation beams to offer but they all serve the same purpose and will generally sit ontop of your base with a DPC in between. This will generally be enough to keep unwanted ingress from entering your cabin but where two foundations beams butt join together you should think about enhancing these connections with a decent sealant/sealer.

Walls Of the cabin

Treatment

Well here we go, We are starting to get into this now as once the walls are up you can finally start to get a good feel for your log cabin, as we mentioned before the walls are made from individual logs stacked ontop of one another to from a very solid wall, They interlock in the corners with fancy Wind and Weather Proof Connections which go along way to ensure that your cabin remains water tight… But as we also explain this isn’t where the story ends and you cannot just leave the logs as as they are and expect the building to be watertight which leads us swiftly onto a very important part of maintaining your log cabin which is TREATMENT

So let’s start by asking a question.. What is Wood?

Wood is basically a Sponge and this is how you must treat each individual part of your cabin, if you zoom right into the endgrain you will see that it’s made from straws all joined together which was once used to draw water and nutrients to the parts of the poor tree that once needed it.

Wood is a sponge and is made up of straws all drawing water for the tree.
Wood is a sponge and is made up of straws all drawing water for the tree

You can easily see from these pictures that when we look closely, wood is full of holes and it’s these little buggers that will be causing a problem as they all fill with water or, drain of water as seeing as we killed the poor thing there is no tension of water to rely on.

For an untreated piece of wood especially this is happening constantly, it’s trying to reach the same moisture content as the surrounding air. This is known a Relative Humidity and is a measurement of the amount of moisture in the air around us.

In the summer the wood will expel moisture and shrink, In the winter they will absorb moisture and swell which will loosen and tighten the joints where the logs interlock.

Prevention

A lot of customers will fairly just assume that “treatment” is only applied to safeguard the wood, stop it from rotting ect but in truth this is just one of its benefits. Treatment is also there to try and limit this natural movement as much as possible , We want to limit the amount those sponges can absorb and expel moisture by clogging up the straws contained with in.. we do this by reaching the recommended depth of microns.

A decent treatment should provide the following benefits

  • Protect the surface from weathering (including UV damage)
  • Seal wood on wood joints with in the cabins construction
  • Reach the required micon depth ( 80-120 microns ) which helps limit natural movement
  • Provide the desired finish for appearance

More information on Treatment specifically can be found within the other support articles we offer

I hope the above all makes sense as it then leads on to the ongoing maintenance of your cabins walls. They must be treated and they must be treated well, please do not expect to only have to treat your building once throughout its life time and Please Please Please use a decent treatment in the first place.. To many times have we had angry customers over the phone shouting, screaming at how dreadful it all is and how disappointed they have become….to only find that they hadn’t applied enough coats, hadn’t kept up with the re-treatments or instead used a lets say “less expensive” brand in the first place.

We recommend our own Tuin Treatments or specific ones found locally such as Sikkens, Sadolins and Kingfisher which we know work well at achieving the desired depth of penetration.

You will not cut the movement out entirely which is fine because the building is designed to handle a certain amount without any fuss.

So as the logs of the cabin move ( which they will ) you may then need to re-treat certain areas of your walls, Paying particular attention to the end grain and interlocking notches where they join another wall, these are the most vulnerable parts. You will also need to make note and follow the manufacturer’s guidelines in terms of reapplying dates.

Overgrowth around the cabin.

This part is mainly aimed towards landscaping and storage rather than the cabin itself.

I’ll start by repeating one of our Bold Statements that we confidently make, Wood will never Rot … we promise… Well, we also go onto say that so long as it is always ventilated, . so if it gets wet and is then allowed to dry it will be fine.

but what if it can’t dry?, What if air can never reach some parts of your cabin due to overgrowth, shrubbery, stacked rocks, Muck ect…

Or what if you decide to store things right up against the side of the cabins wall such as logs for a burner and leave them there for a few years while they season..

All of a sudden the wood cannot vent and dry, Water could then sit there all winter which will eventually cause you all sorts of grief

Please be mindful of your walls, Make sure they are free from direct contact with anything which could cause a water trap, keep ontop of your gardening in those hard to reach areas as if you allow overgrowth to take over it can really ruin your day… you may even decide to call us.. complaining about the timber quality in the first place… “sorry but its wood” we will tell you.. “it only rots if its not allowed to vent” we will try and explain… you won’t like that.

A Daisy log cabin free on all sides allowing decent circulation

Movement In log cabins

As we know by now the walls of the cabin move as the logs Expand and Contract throughout the seasons, the design allows for that just fine.

But what if you want to fix something to the wall like a mounted TV bracket or some shelving to store those garden tools.. I always tell people they can do whatever they like to these types of buildings so long as they follow the golden rule which is.. “You must always allow for vertical movement with in the logs” further explained with in our Dealing with Expansion and Contraction page

Another consideration for some, if your cabin happens to feature vertical posts that supports a canopy or large overhang you will need to periodically check that the adjustable post anchor that we supplied is set at the right height to match the rest of the cabin.

So let’s say you happen to own a building like out Kennet log Cabin

Our 28mm Kennet Log cabin

Remembering that the wall logs expand and contract, that front post will need to be adjusted from time to time as the seasons change becuase it will not move to the same extent, This is achieved by simply adjusting the nut that sits beneath the smaller plate on the anchor.

Post support being adjusted

Doors and windows

I think the best way to approach this section will be to start by gently reminding you that just like the walls, The doors and windows are predominantly made from wood, you remember all of those straws?.. Sponges.. yup this wood is no different

Sure,..the doors and windows tend to be made from timbers which are laminated together which does improve their strength and reduces the possibility of movement but its still wood and it still has those straws.

Treatment

The correct treatment of the wall logs is very important.. but I would personally say that the correct treatment of the doors and windows is even more so and here’s why

Unlike the logs, The doors and windows do not have the same luxury of being fully and always supported.. The wall logs are locked in place and would do well to move in any unexpected sense.. but the same cannot be said for the swinging doors and windows… they are only connected to the cabin via hinges which means if the level of treatment isn’t correct or sufficient you may eventually encounter unwanted warps or twists to occur making them much harder to operate.

When first delivered the doors and windows normally arrive deep with in the pallet, This is on purpose as it provides needed support and compression while in an untreated state to prevent warps and twists… but at the very least the pallets are always banded tightly.

Doors packed within a log cabin package to protect them especially from warping
Doors packaged with in the log cabin package to provide compression, preventing movement

You then unpack the doors and windows, Please store them flat and again under compression until ready for installation and treatment. While in situ you need to be very attentive with your treatment and often customers will not give them the attention they sorely require. Treatment should be applied both sides evenly and heavily.. To many times we have had customers upset becuase their doors have warped and to find out after that they didn’t treat it fully or correctly..

An extremely warped door.
A very twisted door, Do we think this was stored correctly prior to installation?

Hardware

Luckily, even the most twisted door can be corrected with the simple application of a Turn Button or Key,.. you would of already seen these in action in gardens throughout your life time i’m sure as we explain within our other Support Page so don’t panic too much but like most things prevention is better than a cure.

Please keep ontop of your door and window treatment.

Let’s move onto those hinges that we mentioned earlier, The doors and windows will come with their own style of hinges so you can operate and use them.. A lot of the time they are cup hinges that look similar to this

Two piece hinge forming a cup and spiggot. These can adjust the door in both planes.
Typical Cup Hinges

Now remembering what we discussed before, while treatment will limit the amount those pesky straws can absorb and expel moisture.. it will not cut it out entirely. You will at some point need to adjust the hinges of your doors and windows so please expect to do so, We go into more detail about this with in our other Support Page

A lot of the windows we send are top hung which operate from the inside via a simple Window Stay, we have all seen them and they do the job nicely

Its always easier to pre-treat the windows and doors before they are fitted so you can be sure of full coverage but sometimes this isn’t always possible. or perhaps it’s just time to recoat them following the manufacturer’s guidelines.

Common type of top hung window on our Emma Log cabin

If you find yourself having to unhang this type of window from the cabin please be aware of an important Safety point before you proceed. The hinges are only designed to keep the window in place with in the constraints of the supplied window stay which means if you lift it up further, the hanging part which contains the glass could slide off. Be ready to take the weight and seek help from another if needed.

Be careful when lifting the window beyond the stay limitations

While on the subject of door/window furniture, let’s also talk briefly about the actual locking parts, The cylinder, mechanism, latches ect

These are pretty much self contained but some considerations should be made such as occasionally adding some lubricant with in the metal workings so everything operates as it should.. you don’t want the metal parts seizing up.. also consider oiling the exposed elements to keep rust and corrosion at bay.

Also think about fitting a traditional hook and eye’s for your doors so that during use you can keep them securely open, what we don’t want is the wind catching your new doors and smashing them against the walls… thats how things break which nobody wants.

Hook and Eyes being used on our Chloe log cabin

Glass

That’s about it for the actual hardware, but what about the glass that lets in that sought after natural lighting.. what do we possibly need to consider in terms of maintenance.

The panes of glass are dry fitted into a rebate contained with in the door or window, this is all done prior to delivery as it’s much safer to transport while in place.

The panes of glass can always be accessed if ever needed, they’re only held in by wooden beading which can be Removed With Ease

Glass held in place with removable wooden beading

There’s a few things that we need to think about and one of them which is often not really considered is the seal between the glass and that wooden beading.. is it sufficient?

Going back to treatment by this point you will have fully treated both sides of your window or door right up to the glass.. This alone will typically be enough to prevent water from encroaching between the two surfaces and finding a way into the cabin.

You may also ask yourself, Surely they will come pre-sealed in some way right.. why wouldn’t they be…..?!

Well actually no, they do not. The glass is just dry fitted inside the rebate of frame… thats not becuase we couldn’t be bothered or we’re just trying to save a few pennies on some silicone here in the office to keep the accountants off our backs. It is dry fitted for good reasons!

Firstly, While the packing team do their best to pack the pallets in the safest way possible, we are talking about several tons of a log cabin being moved around and transported over huge distances by several hauliers so things can happen and your glass could arrive damaged ( rare but possible ) .. its glass.. it can break!

For those of you that have used silicone before you will know that it can act abit like glue at times.. so in the unlikely event that you receive your cabin and some of the glass is broken its then an absolute nightmare and down right dangerous to go around and dislodge the broken shards from the inner frame and in the past when units were delivered pre-sealed we received right ear falls from angry customers and rightly so.

Hopefully you agree and can see why we do not send them out pre-sealed, So once you have treated the frames in full and you then go on to notice ingress, all you need to do is either run some sealant along where the glass meets the exterior beading… or if you want you can remove the beading and silicone where the glass directly fits into the inner rebate instead.

Refitting the glass is the reverse of taking it out. If you wished to you could add a bead of silicone sealant although this is not necessary.
Silicone being added with in the rebate

Movement in log cabins

Moving on slightly, Let’s think about how the frames actually fit into the walls of the cabin for a moment

Back to Movement again ( sorry ) The door and window frames are made with dry, fixing free U-channels which slot over the wall logs which means they will not constrict anything as it moves.

The U-channels are formed by what we call fascia boards… some call them architraves.. they’re basically just planks of wood screwed to the frame to create the U shape. These cover up the all important expansion and contraction gaps which are left above and to the sides of the frames ( please do not in-fill these gaps with anything )

Fascia boards fixed to the perimeter of the frame to create a U-Channel

So a few things we need to consider in terms of ongoing maintenance,

Have the inner sides of the fascias been treated correctly, fully? ..Well they should be as they also play a good part of sealing the outer perimeter of the frames.

Have you accidently sent fixings through these fascias which then also penetrate the moving wall logs underneath?.. if so please remove them as you will be preventing those logs from moving with the rest and you will most likely end up with gaps in between those logs.

Or, Perhaps you have noticed gaps around the door frame but are pretty adamant that there are no fouling fixings.. Try loosening the fascias and then re-tightening them.. if that doesn’t work then send us some pictures so we can have a look with you.

Maybe you have treated the underside of these fascias but you have noticed some signs of ingress? In this situation we may just need to enhance the seal between the two wooden surfaces.. Removing the fascias and adding silicone or draft excluders will normally cut that right out .. Just let us know and we are happy to send you some FOC.

Log cabin Extras

We can provide an array of Log Cabin Extras to complement your log cabin and their requirement depends mostly on the circumstance

Before we touched upon the importance of Ventilation which helps prevent moisture from building up within the sealed cabin, If you are not constantly in and out of your building should consider adding Air Vents to allow a continuous flow of air in and out of the building.

Also think about what you store within the cabin, White goods especially kick out a lot of moisture so be sure to install vents to combat that.

We also offer Storm kits as an extra, These are spring loaded metal rods which are used to ensure that the roof of the cabin remains tied down to the rest underneath, most applicable to those in very exposed areas or for those cabins with large exposed canopy/overhangs… please consider the application of a Storm kit

Shingle Glue is an option to consider, Very handy again for customers in exposed areas but generally if you are installing in the winter it is suggested to safeguard the shingles until you summer next rolls around.

We highly recommend Guttering for your log cabin, Not only will this help filter roof water to the desired location it will also serves in protecting the walls and perimeter further down from unwanted ingress and splash around the base.

We also sell a product which is very useful for coating the inside of the walls, Its called Impregnation Fluid on the website and is a very powerful Anti-rot, insecticidal treatment which you could consider, Please note that in inside of your doors and windows will need more than just this product alone.

The Roof

The roofs on these cabins should really be pretty self contained, so long as the roofing material was installed correctly there isn’t really that much you should ever need to think about.

Just keep an eye on any unwanted growth ontop, Moss can sometimes start to build up which should be removed as and when you can. Overgrowth can prevent the surface from ever drying out fully… also if you happen to install the cabin in the winter and moss manages to build up before the summer comes back around it could limit the amount of heat that gets to the tiles which is needed to bound all the those bitumen strips together.

An old log cabin shingled roof
Serious overgrowth, Overdue a clear out we think

It will also be a good idea to periodically check underneath the roofs fascias for any nests which long term could start damaging the wood.

before those fascias are even applied they should be pre-treated as they are hard to reach once installed, Just like the other parts of the cabin you will need to revisit the treatment after a set timeframe and these higher parts are easily forgotten about and missed.

We hope this helps and we are happy to answer any unanswered queries that may come to mind, Please also revisit our installation manual for much much more.

Summary

  • Keep half a mind for your Base, Check the levels if you start to notice anything strange happening with the cabin on top
  • If you start to experience high levels of condensation within the building consider checking your damp proofing and joints between the foundation beams.
  • Remember that wood is a sponge, Keep on top of your treatment and please use something decent., Recoat those vulnerable areas and meet the guidelines set out on the tin.
  • Treat the doors and windows well and frequently
  • Fit hook and eyes to your doors to prevent unwanted wind damage
  • Keep your green fingers busy, Stop overgrowth from taking over and allow air to fully circulate around the cabin.
  • Do not create water traps around the walls of the cabin
  • Be mindful when fixing anything to the walls, Remembering your cabin likes to move
  • If you find water ingressing around the glass, they need sealing further
  • Guttering should always be fitted to better protect your cabin
  • Add Air Vents to prevent the build up of moisture
  • Consider the need for other log cabin extras
  • keep half an eye on your roof, remove overgrowth frequently

 

Expansion in Log Cabins

Two Extremes with Log Cabins

There are two extremes of the year in a log cabins first year of life; The height of Summer and the depths of Winter. Both of these times may possibly cause problems for you depending on the level of treatment you gave your cabin when you installed it. These problems will generally only be noticeable in the first year cycle of a newly built log cabin as I explain in the articles referenced below.

The problems are one of either expansion or contraction of the wall logs that make up your log cabin.

But, with that said you should never, ever notice this movement, such is the design of most log cabins. The building will grow and shrink un-noticed by you…..

BUT ….. only if it has been built, treated, and vented correctly and also with the correct layer of damp proof membrane on top of or within the base. The correct treatment though cannot be stressed enough, as it will inhibit both these natural features of wood and you will never have a problem or even notice what your log cabin is doing over the seasons.

Contraction of logs in your log cabin – Summer

In the summer we will see contraction and I have written a lot about it in a previous article: Moisture Content of a Log Cabin and Depth of Treatment this article is helpful as it explains the intake and expulsion of moisture from the relative humidity and explains how each log can expand and contract by as much as around 3 – 5mm per log. Over the course of a building log height you have a potential movement of about 80mm, that’s about 3 inches! Sometimes it will be more if the building has received little or no treatment and within its first 12 months of being installed.

A second article which will interest you on the subject of timber movement within a log cabin is: Contraction of a Log Cabin this article explains what can happen in the height of summer, and when a log cabin has had little or no treatment.

Expansion of logs in your log cabin – Winter

Here are some examples of problems that may occur, all of which are down to the natural expansion of timber within the winter months, most of which could be avoided with treatment, damp proof membrane and in some cases ventilation and correct installation of your log cabin.

White bits:

The most common area that you will notice with expansion in your log cabin is when white bits start appearing.

Classic winter expansion of logs in a log cabin – notice the bare wood appearing above the door fascia

Expansion of the logs has caused bare wood to appear from behind the window fascia

For log cabins built around July, August, September and a little later this is fairly common to see and is entirely normal. This is happening as the logs are inherently a sponge and made up of 1000’s of straws which of course the tree used to suck up water from the ground, this is what is happening with the logs during the winter months, they are sucking in moisture and expanding.

This is entirely normal and one that can be easily inhibited by the correct application of a good quality treatment. We also advise in our Log Cabin Treatment Advice article that when treating your log cabin to also paint behind the fascias to the side and above and you will then never notice this expansion taking place at all. If correctly treated it may not even take place at all!

Wood is made up of 1000’s of straws, all of them are designed to suck up moisture from the ground. In the correct treatment of a log cabin our aim is to block these straws as much as possible to inhibit the natural expansion and contraction

Gaps Appearing

During the summer months we can sometimes see gaps appearing if the cabin is not treated well of built correctly. During the winter we can very occasionally see another form of gap appearing and this is generally above the door.

A gap has started to appear above the door as the logs have expanded so much the contraction space has started to appear.

We have seen this a few times in extreme cases, this is very easily solved with a shim placed under the door and the checklist at the bottom of this article followed come the warmer months.

Frames Apart

In our Log Cabin installation advice page and also the instructions that come with all log cabins we do try to get across the importance of NOT fixing anything across two or more logs, including the doors and window frame and fascias as the wall logs need to be able to move independently due to their contraction and expansion. Sometimes though this advice is not followed.

If door or window fascias are fixed to wall logs you can see the expansion of the logs may force the frames apart – never fix log together or inhibit their natural movement!

Fixing fascia that are attached to the top logs to the door frame can be pulled apart by the expansion force.

This door frame is being pulled apart as the top fascia has been fixed to the top wall log, as the logs expand the top part of the frame is pulled upwards by considerable expansion force.

Below is another good example of the door frame being pulled apart from the top fascia being fixed to the wall log. See how evident the rogue screw is, as well as how much expansion has been caused from the force the screw has created:

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Floor and Roof

The floor and roof of your log cabin is also affected by expansion and contraction and as we advise it is important to consider the time of year you are installing, at the height of summer you will need to ensure you leave a small expansion gap between the boards. In the case of the floor it is very important to leave room for expansion all around so the floor does not push against the sides of the log cabin.

It is very important to leave an expansion gap all the way around the floor as highlighted in our installation advice, this will then avoid a roof, or floor, from rippling when the winter comes.

Treatment

It is always at this time of year that we get a series of complaints that all can be traced back to treatment, I wrote this article at the same time last year: Log Cabin Treatment Gone Wrong this highlights a lot of the issues when treatment is not correctly applied or the good quality treatment used.

Log cabin treatment gone wrong

If our advice has not been followed regarding treatment it is the height of winter when it will become most obvious.

Problems with treatment will not only manifest itself by unsightly marks as above but you may also have leaks in extreme driving rain conditions. The is due to ineffective or cheap treatment being used which then cracks and allows water to ingress via capillary action. This can also be caused by treatment not being applied correctly, particularly one of the cheaper shade treatment requires light sanding, wiping with spirits and at the least two coats applied within a few hours to be effective, the manufacturer goes on to state that with dry wood three coats should be applied, it is often overlooked as well that a wood preservative is required under many cheaper treatments. Without following any manufacturers explicit instructions any treatment will be ineffective and problems during at least the first year of a log cabin life can be expected.  We would recommend at least four coats of any treatment correctly used. For more advise on this please see: Log Cabin Treatment Advice.

Water Ingress

There are a number of reasons for water ingress, the most likely is lack of treatment, a poor quality treatment or an ineffective treatment, especially in the corners and importantly on the end grain, this is particularly important to stop tracking of water via capillary action via the grooves in the profile of the logs.

Capillary action can allow a weap to follow the logs in a building that has not fully settled or been treated carefully in the corners, tongue and groove or the end grain.

Little or no treatment has been applied to this log cabin. Water marks are now becoming evident in the corners and some mould build up on the door.

As I have mentioned before. Wood is made to act like a sponge. If it is not treated correctly it will absorb water by its nature. This door did not receive a very good level of treatment and over the course of a year has absorbed a lot of water. A great deal of this could have been avoided with a good treatment and of course ventilation within the cabin if it is closed up for long periods of time.

Until a building has fully settled over a period of a year and gone through it’s various cycles it is possible to have driving rain force into the corner joints. BUT, this is very easily prevented by the correct application of a good quality treatment as all the joints are sealed.

Water ingress along the bottom few logs pushed via driving rain. A good quality treatment correctly applied prevents this. I have noticed that some pictures of issues will show this area more often. As can seen from a treatment picture further up this post the lower part of the cabin is missed, possibly as it is harder to treat due to bending over? It may also be that this area takes more driving weather? I think though from experience it would be a good idea to concentrate on this area if you think the log cabin is exposed when you treat it.

Condensation

Condensation is occasionally overlooked and this can affect your building greatly. As we advise it is vitally important that a damp proof membrane is incorporated within your base on top of it. Advice on this can be found in our Log Cabin installation advice article.

Even with a DPM, condensation can still build up in your log cabin if it is not regularly used, in this case it is highly advisable to fit some sort of vent. More advice can be found in our Ventilation in Log Cabins article.

As well as ingress from outside it is possible for condensation to build up inside a cabin if not regularly used or ventilated.

Condensation can also manifest itself as damp spores on the roof and walls. This is a mild case but the building does need some sort of ventilation when closed up for long periods.

On a larger scale, especially when a DPM is not fitted so much moisture can be built up it actually looks as if there is a leak in the roof. Ventilation will resolve this problem.

Doors and Windows

Last night I had an email from a friend who said ‘don’t go around the back to the conservatory door as it’s stuck, it’s always like that when its cold’. I smiled to myself, of course it has nothing to do with the cold, it’s everything to do with treatment and inhibiting the expansion of the wood in her patio doors. It’s exactly the same with a log cabin door set and windows, they will react in exactly the same way if they do not have enough layers of good quality treatment applied.

Doors and windows, if not treated well enough and certainly within the first year, may expand and could become tight in the frame. Ideally doors and windows should be treated both inside and outside to guard against expansion and contraction which can in turn cause warps in a frame

Summary of Expansion in your Log Cabin

All the above points affect any log cabin no matter the manufacturer and indeed any timber structure both inside and outside of your home.

If you have any of these issues, please do not worry, they can all be solved easily.

  • White Bits: This is the easiest to solve, wait until the weather improves and then remove the fascia, you can then paint behind them and you will never notice this again.
  • Gaps appearing above your doors or above the windows. This is easily solved by raising the door or window frame and then inserting a packer the length of the frame. The gap will then be hidden behind the fascia. You will need to remember you did this and consider removing it in the Spring when the log cabin starts to contract again.
  • Frames or trim parting: It is very likely that fascia or frames have been attached somehow to the logs. Please remove any fixings you can find. Doors and windows can easily be removed by taking off the fascia, please then make sure the whole frame is refixed together and reinstall. Do NOT fix any part of it to the wall logs or trim mounted on the corner triangle (in the case of corner log cabins)
  • Floor and Roof: This will be a little trickier to solve. For the roof I have found more nails can be added and it is generally enough to solve the problem as it can still expand across the whole length. The floor maybe pushing against the wall logs, check for this and if it is the case you must create an expansion gap all the way around. A jig saw will be able to accomplish this. In extreme cases you may need to consider a whole new replacement floor.
  • Water Ingress: This one is a little trickier during the winter months and it is probably best to leave it until the warmer Spring months. You will need to review your treatment process and what you used. For cheaper shade treatments you will have sanded the walls, washed it with white spirit, applied a preservative, then applied at least three coats in batches of 4 – 5 hours. Better treatments such as Sikkens and ours will generally need three coats, sometimes an undercoat is also required. For our carefree protect treatment this can be applied direct and built up to three – four coats over a number of days for full protection. Make sure you have read and fully actioned the manufacturers instructions. Please see our depth of treatment article for more advice. You will need to consider re-treating your log cabin and also upgrading the treatment you originally applied. As we advise, if you use a top quality treatment, correctly applied these problems are unlikely to occur. The first thing, by eye you can notice if a treatment is a good quality is ….. is there stretching of the treatment across the joints over the winter? You can often see this, a cheap treatment will simply crack and that is when ingress can occur through capillary action. Look out for this!
  • Condensation: Please check an effective and un-punctured DPM has been applied within or on top of your base. This is your first port of call for a condensation problem. If you are not sure or one has not been applied the floor will need to be lifted and one fitting. If it has and the building is closed for long periods over the Autumn and Winter please consider adding at least one vent into your building. More advice can be found here: Ventilation in Log Cabins
  • Doors and Windows: On most of our log cabins the hinges can be adjusted to account for this, please see this page for advice: Log Cabin Doors you will also need to consider the treatment advice above, ideally doors and windows will be treated equally both inside and outside.

First Year of Life! 

It’s odd but after a year and completing the cycle a log cabin seems to settle down a lot, I think it is because the straws in the wood make up has dropped, crushed or have been blocked, after a year all these things seem to settle and almost disappear.

Some of the above may have left marks or stains which take away from the aesthetics of you building, however, all is not lost and can be easily cleaned again, please see this page for advice: Cleaning a Log Cabin

Dealing with Expansion / Contraction in Log Cabins

We know that Log Cabins move and certainly within the first year of life they can move quite a bit. I explain this in an article about moisture content in log cabins which greatly effects the expansion and contraction of the wall logs.

The trouble is this movement can be a bit of a problem if we want to put things on the wall, or perhaps adding some shelves or fixing machinery. You may even want to partition a portion of your cabin for several reasons, perhaps you want a shower or a toilet or just a separate storage area. You might also want a thinner log building due to your budget but you would like to insulate the walls to use it as a garden office.

All of this can be done easily but to do so we need to keep fully in the front of our minds that the bloomin’ thing will move and we don’t want to stop it.  If we do inhibit this natural movement we can end up with all sorts of horrible things happening such as:

  • Splits in the logs – This will normally be caused by logs being held together
  • Gaps appearing where logs have been held – normally by a window frame being screwed to the logs
  • Moisture entering through gaps and splits

To avoid all these problems, if we want to fix anything to a log cabin wall this is the simplest and best thing to use:

Expansion Slat for Log Cabins

Expansion slat for use in a log cabin to still allow movement of the logs.

Expansion slat for use in a log cabin to still allow movement of the logs.

This is a handy bit of wood and you can make it out of left over floorboards or roof boards. Any timber will suffice though and you will pick the thickness depending on the job you want it to do.

I often advise customers to make these for use as storm braces when they are in exposed locations, off cuts from the roof or floor boards is fine to use and you then position them behind the corner interlocks so they’re not really seen. This slat will then be fixed to the top most log and the bottom of the slat to a lower log, this then ties the whole cabin together.

The very simple principle here is that we have one fixed hole at the top and slots in the middle and end (depending on the length). The top hole is screwed tight and using a washer the slot fixings are not tightened fully so we can still allow the logs to move behind the bracket.

Shelf Fixing in a Log Cabin

Using this system you can put up shelves, cupboards and fix tools to the walls:

Expansion slats for fixing things to the walls.

Expansion slats for fixing things to the walls. Using this slat will allow the logs to still expand and contract.

You will see from my diagram that we are fixing the shelves to the expansion slat and not to the logs. For heavier duty uses you may want a thicker slat and you may want to bolt it fully through the log cabin wall.

This is also needed for securing cupboards to the walls and especially useful for electricians when securing a consumer unit.

NOTE: in the first month or so a log cabin will settle quite a bit from first being erected so it’s best to leave it for a few weeks before adding brackets and securing fittings. Within the first year the cabin will move the most as the wood needs to ‘die’ a little more. Year two will be a little less. Years three, four and onwards the movement is hugely reduced. Also remember the most important thing with a log cabin is to properly treat it. Proper treatment with a good depth of treatment will greatly inhibit the natural contraction and expansion and reduce it to a minimum. More details on Treating a log cabin

Partition Walls in Log Cabins

The same as you do in your home you may wish to put a partition wall into your log cabin for any number of reasons. You can do so as long as you remember the log cabin is always moving!

Using the simple principle of the ‘expansion slat’ explained above we can create slots in framing and make a wall as any stud wall would be made remember though the slot fixing should not be fully tight and always allow the logs to still move in both contraction and expansion.

Partition wall framing in a log cabin

Partition wall framing in a log cabin

You would make a partition wall as you would any stud wall and probably with noggins for extra strength. Your final surface covering could be anything you would like including plasterboard. However, if the floor has already been laid do not fix it to the floor as like the wall logs the floor will be expanding and contracting as well.

Twin-Skin Log Cabins

You may have seen twin skin log cabins in the market. I’ve put a couple of these up and they really are a challenge and I don’t like them for a number of reasons. Mainly the design intent is all wrong but I will not expand further here. If you require my personal thoughts please feel free to ask me.

Instead of a twin skin design I prefer making an inner wall and one that is independent to the main log cabin wall. This is particularly useful if you are constrained by your budget and want an insulated log cabin but don’t want to opt for thicker logs.

Also, if you are obtaining building control approval because you intend living in the cabin then it will need to be insulated to building standards. Thicker logs certainly help with insulation but sometimes a control officer will want more. I’ve been involved with several projects and a building officer will often ask for 50 – 100mm thick insulation in the walls (depending on the log thickness) and 100mm in the roof with 70mm in the floor. The roof and floor is easier as I make mention here: Insulating the floor and roof of a Log Cabin.

It’s completely fine to add an inner wall to your cabin and fill the cavity with insulation as long as you constantly bear in mind that the logs of the log cabin itself are always moving as previously explained.

NOTE: Also though consider what you are going to do where the logs join the roof, we cannot restrict the contraction and if the cabin is dropping over the summer if you have not allowed enough room the roof could end up sitting on your internal frame causing a gap to be formed.

Allow for the contraction as well as expansion!

This explains how you can create an internal wall to allow insulation inside the log cabin:

Creating a twin wall log cabin

Creating a twin wall log cabin using the same expansion slat principle

Using the same principle with the expansion slat we can create framing internally against the wall. The frame will of course depend on the depth of insulation required but employ the same methods and remember the logs need to move independently.

Building control will ask for a breathable membrane, followed by a small air gap, and then the insulation in between the frame. On top of the frame you will place your surface covering. Timber logs of 28mm looks good or use a thinner cladding for economy or perhaps plasterboard for a smooth sleek, modern finish.

I normally like to insulate the roof on the outside and this can still be done if you are lining the walls on. The reasons I like it on top of the roof is:

  • It’s generally easier and quicker
  • It’s less expensive
  • No cavity is formed to collect condensation

If you are cladding the inside in timber and putting insulation on top of the roof you will still maintain the look and feel of a log cabin and benefit from the space the vaulted roof provides.

This is an example of insulation on top of the roof:

Insulation added on top of the roof with inner wall insulation

Insulation added on top of the roof with inner wall insulation

Make sure you allow enough room for contraction. With this example you can see I am keeping the inner framing below the roof boards as with contraction there is a chance the boards could sit on top of the frame making the wall logs  separate.

I’ve used a fascia suspended from the ceiling that will sit in front of the inner wall but is not connected to it allowing it move up and down as the log cabin expands and contracts. Fill any cavity created with fibreglass insulation wool so it can also move.

In a previous article on roof insulation I was recommending 40mm – 50mm thick insulation.  If you are going to use thicker which you may want to, you would need to ‘cell’ the roof and board on top of the insulation:

Using timber framing to cell the roof and infill with insulation boards

Using timber framing to cell the roof and infill with insulation boards

Some building control officers will ask for 100mm in the roof. To do this you will need to create a tray on the roof, then cell the tray and put in the insulation board with a final board on top and then the final roofing material. You may also wish to consider adding a breathable membrane.

If you wish to insulate under the cabin roof you could so within the purlins and then clad underneath them:

Using insulation in between the roof purlins

Using insulation in between the roof purlins

Another method you could consider is as follows:

Creating a ceiling within a log cabin

Creating a ceiling within a log cabin

Again like the methods above we are making sure there is enough room for expansion and contraction of the outer wall logs.

Please remember, if you create any voids to really consider venting them as a buildup of condensation can cause huge problems.

Summary of Dealing with Expansion in Log Cabins

Log cabins are an extremely versatile building and are very inexpensive and they can be used for any number of uses from a humble garden shed all the way up to full blown family accommodation.  They will all behave the same and will all move all the time. So long as you remember and allow for this you can do anything you want to them. Including partition walls and internal insulating walls as I have shown.

Please Note: These are ideas for you to take away and use how you will, these are not detailed plans with measurements and the drawings are NOT to scale. If you go on to carry out any of these ideas please let me know how you get on but this is not a simple DIY task and you will need some knowledge and understanding of the processes and materials involved.

One last thing; the windows and doors are also part of the outside wall so don’t join any of your internal framing to the doors or windows in anyway, treat them exactly the same as the logs.

Please ask me any questions you have on this or if you do use my ideas, please let us all know how you got on. Like the timber frame bases for log cabins none of this has a hard and fast rule except: Log cabins;  Move!