Not exactly off topic, slot together shed/cabin repairs

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whatknot

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My neighbour has inherited a slot together shed/cabin when she bought the house, it had only been up a couple of years then, now its a further five years old

The problem is its not been put up on a flat base (although its a slabbed base) and has gradually dropped it appears at the front end leaving gaps in places on the side between some of the slats, some 20mm or so (ie no gap at the rear 20mm at the front)

Without taking it apart and rebuilding it which is not really an option, what could anyone suggest be used to fill the gaps left?

I thought of expanding foam, painted over to seal from the sun

Not sure what else to suggest to her

The attached are just to show the type of construction, her cabin/shed is similar to the constructed one
 

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Hard to comment without pics of actual cabin and said gaps . If the base is failing it could be that the slabs were not laid correctly or even worse the ground underneath is not stable . Mho based on what you have posted is the route cause needs to be addressed before attempting any repairs- you’ve ruled out the most obvious which I understand but it maybe the best solution especially if the ground / base is unstable. Last year I went to quote for erecting a similar cabin but walked away when the customer showed me the base her Gardner had prepared. 1” of gravel over 2” of sharp sand and tamped down with the back of a shovel .
 
backer rod + caulk that is flexible, it should be able to move without cracks appearing, obviously depends how big the gaps are.
 
If the gaps have appeared because the base has dropped, undrop the base by jacking it up and inserting suitable packers.

If it is empty, door lifting airbags might do it.

https://www.buybrandtools.com/acatalog/winbag-max-inflatable-lifting-device.html
The risk is that raising it does nothing to close the gaps. In that case, some long threaded rods and timbers to clamp roof and base together would squeeze it shut.
 
Hard to comment without pics of actual cabin and said gaps . If the base is failing it could be that the slabs were not laid correctly or even worse the ground underneath is not stable . Mho based on what you have posted is the route cause needs to be addressed before attempting any repairs- you’ve ruled out the most obvious which I understand but it maybe the best solution especially if the ground / base is unstable. Last year I went to quote for erecting a similar cabin but walked away when the customer showed me the base her Gardner had prepared. 1” of gravel over 2” of sharp sand and tamped down with the back of a shovel .

Thanks for your reply, but no the base is firm and solid, basically they used the existing patio which was firm and solid but had been erected some years ago with a slight slope to let any rain water run off, the base has no cracks or loose flags, I can't see any movement at all in the base but they built the cabin direct onto the sloping base

It was fine at first but gradually its tried to find the level so the front of the cabin has dropped leaving gaps to large to put fillets in (its also tongue & grooved)

So all I could think of was to dismantle and rebuild the cabin after levelling the base, but the owner is a lady pensioner and I am past the point of such adventures ;-)

So my only other thought was expanding foam and paint over it once trimmed, not ideal I admit but at least might keep the weather out for a while
 
If the gaps have appeared because the base has dropped, undrop the base by jacking it up and inserting suitable packers.

If it is empty, door lifting airbags might do it.

https://www.buybrandtools.com/acatalog/winbag-max-inflatable-lifting-device.html
The risk is that raising it does nothing to close the gaps. In that case, some long threaded rods and timbers to clamp roof and base together would squeeze it shut.

No the base is solid, I can't see any cracks or movement in it, it was erected more than 26 years ago as it was there when we moved in

Its been long in use, has a tumble dryer and washing machine in it as well as the accumulated stuff of five years, so would take a lot of effort to empty it

I know those bags well, very useful, got me out of a hole when I managed to lock my keys in my car at my sisters funeral

I had thought of trying to jack the base up and put chocks in and if the gaps can be reduced fix batons on the inside top to bottom but suspect it would be a case of jack one point and find more gaps somewhere else
 
Sadly the gaps are to big for caulk

By backer rod do you mean vertically roof to floor? or ?
the backer rod is a polystyrene round shape that fits into the gaps, you can buy it in any size, but buy it slightly larger than the gap you want to fill so it compresses a bit, it just fills in the gaps then you go over it with caulk or silicone, also saves money on caulk because it takes up most of the space, it can also move with expansion and contraction without cracking the caulk over time, I used it when soundproofing my recording studio and it works extremely well at creating airtight seals.
 
I have log cabins, the timbers are much thicker (and therefore heavier) than a standard shed, eg: shiplap boards, etc. So the bases have to be able to take the weight. As suggested above I'd look at possibly jacking it up, and installing packers, if the base is ok, or compressing the whole thing, using threaded bar.
 
You can use those swimming pool noodle things as "backer rods"..cheap..or even cheaper.. scavenge some of the polystyrene packers that come with delivered fridges etc..local white goods sellers will probably have a skip full around the back if you ask nicely and tell them it's to help out an old lady.
 
the backer rod is a polystyrene round shape that fits into the gaps, you can buy it in any size, but buy it slightly larger than the gap you want to fill so it compresses a bit, it just fills in the gaps then you go over it with caulk or silicone, also saves money on caulk because it takes up most of the space, it can also move with expansion and contraction without cracking the caulk over time, I used it when soundproofing my recording studio and it works extremely well at creating airtight seals.

Thanks for that, I confess I have never heard of it but can see its usefulness , thanks for the suggestion
 
I have log cabins, the timbers are much thicker (and therefore heavier) than a standard shed, eg: shiplap boards, etc. So the bases have to be able to take the weight. As suggested above I'd look at possibly jacking it up, and installing packers, if the base is ok, or compressing the whole thing, using threaded bar.

Thanks for that, if I were a bit younger I would certainly tackle it but its a bit much now, as I said the base is hard and firm, no movement as far as I can tell, its the way they have erected it on a slight slant that appears to be the problem

And yes the timbers are more substantial than your ordinary shed

If I or anyone did try and jack it up I suspect the floor would droop as you can't get under to support it

I think in this case filling the gaps as best I can is the only thing I can offer my neighbour but appreciate the suggestions made
 
You can use those swimming pool noodle things as "backer rods"..cheap..or even cheaper.. scavenge some of the polystyrene packers that come with delivered fridges etc..local white goods sellers will probably have a skip full around the back if you ask nicely and tell them it's to help out an old lady.

Thanks for the suggestion but think those noodles would be to big, I looked at the backer rod foam suggested and its not to expensive £7 for a 10mtr roll 20mm
 
Thanks for your reply, but no the base is firm and solid, basically they used the existing patio which was firm and solid but had been erected some years ago with a slight slope to let any rain water run off, the base has no cracks or loose flags, I can't see any movement at all in the base but they built the cabin direct onto the sloping base

It was fine at first but gradually its tried to find the level so the front of the cabin has dropped leaving gaps to large to put fillets in (its also tongue & grooved)

So all I could think of was to dismantle and rebuild the cabin after levelling the base, but the owner is a lady pensioner and I am past the point of such adventures ;-)

So my only other thought was expanding foam and paint over it once trimmed, not ideal I admit but at least might keep the weather out for a while
Ok I get you and reading the other replies I,d be inclined to attempt to compress the joints back into each other as suggested by using threaded rod and nuts and bolts securely attached to the highest timber log and the lowest log with a section of angle iron and try simply winding the nut down the length of all thread to literally clamp the whole thing back together to force the joints to close. If it is successful then it may be a case of moving the assembly over and starting again moving progressively along the length of the cabin until you have hopefully closed all the gaps - obviously the floor again as others have mentioned will need packing up to prevent it from happening again. I think with at least two people this can be achieved in a day. I think just patching up the gaps is not going to be very successful especially if the joints continue to open . Not sure what your weather has been like but in the midlands it’s been dry for over a week and as such the joints will be dry and hopefully easier to close. If you were to go this route I’d suggest a minimum all thread of m10 but preferably m12 to cope with the forces involved. Good luck 🤞
 
Ok I get you and reading the other replies I,d be inclined to attempt to compress the joints back into each other as suggested by using threaded rod and nuts and bolts securely attached to the highest timber log and the lowest log with a section of angle iron and try simply winding the nut down the length of all thread to literally clamp the whole thing back together to force the joints to close. If it is successful then it may be a case of moving the assembly over and starting again moving progressively along the length of the cabin until you have hopefully closed all the gaps - obviously the floor again as others have mentioned will need packing up to prevent it from happening again. I think with at least two people this can be achieved in a day. I think just patching up the gaps is not going to be very successful especially if the joints continue to open . Not sure what your weather has been like but in the midlands it’s been dry for over a week and as such the joints will be dry and hopefully easier to close. If you were to go this route I’d suggest a minimum all thread of m10 but preferably m12 to cope with the forces involved. Good luck 🤞

Thanks for your input, I honestly don't know if its within her budget to do that, but may try a test but even finding 10 or 12mm threaded rod that long might be a task in itself
 
Thanks for your input, I honestly don't know if its within her budget to do that, but may try a test but even finding 10 or 12mm threaded rod that long might be a task in itself
Threaded rod readily available in 3 mtr lengths online ,m12 nuts / washers not that expensive but understandable when it comes to the cost -but it’s probably a decent cabin and worth saving given the cost to replace it . A visit to your local scrap yard can pay dividends when it comes to the brackets or angle iron to attach the threaded rod to the cabin walls - you could get lucky 🍀 and find a couple of purpose made brackets ready to go that suit your needs .let us know what you decide and how you get on.
 
Have you put a spirt level on the building to see if it has racked?
I would try a crow bar/air bag first to see if they move back into position, then pack under if they do and sand and cement (dry pack) under the bottom slat to the base.
 
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Threaded rod readily available in 3 mtr lengths online

Your post gave me food for thought.

The difficulty with mail order rod in that length is courier cost. Screwfix and Toolstation have the rod in 1m lengths and you can buy joiners for it. Electrical suppliers (e.g City Electrical Factors) have the rod in 3m lengths.

Anyway, the thought that came after digesting your food is that a ratchet strap would do very well as a squeezer and will coil up with a lot less effort than a steel rod.

A piece of rope tied into a loop and one of those windy Spanish lasses would put manners on it.
 
Your post gave me food for thought.

The difficulty with mail order rod in that length is courier cost. Screwfix and Toolstation have the rod in 1m lengths and you can buy joiners for it. Electrical suppliers (e.g City Electrical Factors) have the rod in 3m lengths.

Anyway, the thought that came after digesting your food is that a ratchet strap would do very well as a squeezer and will coil up with a lot less effort than a steel rod.

A piece of rope tied into a loop and one of those windy Spanish lasses would put manners on it.

Ratchet strap on outside corner then screw a 2x2 inside into each timber.
 
Is there anything fixed to the walls that could restrict movement? It is very dry at present and the logs are likely to have shrunk. Anything fixed to the walls should use slotted holes to allow for movement.
The blogs here are full of useful information.
IIRC one talks about gaps and non-level bases…..

https://www.tuin.co.uk/blog/category/log-cabin-fitting-tips/
If I or anyone did try and jack it up I suspect the floor would droop as you can't get under to support it
If this is constructed as I suspect it might be, it could be a floating floor, separate to the cabin walls (unless the bearers are resting on the foundation beam or fixed to the bottom log of course)
 
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