Timber Garage renovation, focusing on walls now - Need some advice please..

sujsuj

I was focused on my timber Garage renovation for some time. See the other post detailing whats done on roof so far. Now nearly finished roof . Focus now moved to side Timber walls.

Current state of side timber wall is..

• One side was covered with plywood board, which rotten - I am planning to replace this with new timber
• Water/Dampness coming into the garage - this need to be sorted

See photos..

Photo -1) Rotten plywood removed readying for timber cladding
 
Photo-2 & 3 )  Water seepage/wetness inside Garage


Photo-4) Back of garage readying for removing rotten timber, also need to stop water seepage into Garage


Photo-5 ) inside of Garage showing membrane covering



I have following improvement ideas, please give suggestions if there are more things to be done..?

1. Replacing all rotten timber and replace outer plywood shell - Already bought timber form B&Q
2. Planning to paint entire external timber old `& new with bitumen paint - is this a good idea? will it dry in winter? Does it give any more benefits than timber paint?
3. To stop water seepage/wetness from wall  ...(1) planning to cement outer brick layer (2) planning to use bitumen paint on bricks - Any other suggestions..?
4. Any other water proofing material to be applied on side bricks to stop water seepage..?
5. Planning to dig 3 sides (one side is already cemented area) and put a layer of garden tiles - is this a good idea? any other suggestions?
6. Using Airtec Reflective Double Insulation behind all new timber I am putting - Any suggestions?
7. Planning to put thin layer of loft insulation b/n timber cladding & inner plywood to get  more weather proofing 
8. I couldn't find that membrane shown in last photo anywhere... whats that called..?

Any other suggestions/Improvement ideas on this..? My plan is to make the garage weather proof as water was leaking from roof (fixed now) and also when raining water some how get into garage form sides as well.

Doozergirl

I would look at how a timber framed house is built, or even the Oakwood Self Build Garden Room group on facebook which works on similar theory.

Painting in bitumen is not a good idea. Wood needs to breathe and you're preventing it from doing so.   You are better with breather membrane wrapping the outside of your OSB/ply, then battens - one layer (or cross battens depending on the direction of your cladding) then cladding which you can treat.  

Wood isn't waterproof, there's no point trying to make it that way, by sticking waterproof things directly against it and hoping for the best, you just need to keep the water away from the main structure by not letting it get close.  

The other thing is that your floor slab is too low compared to the ground level.  You need at least 150mm from the bottom of your timber to ground level to prevent water ingress and splashback.    Dig around it to lower the ground levels.  Do not bring paving up to the structure, leave a gap, and ensure the direction drains away from the building.  

Apodemus

Yes,  as Doozergirl says, you need to minimise the chances of the wood getting wet in the first place. it looks to me that you need to look at the water run-off from the roof first.  The eaves are not really deep enough to get the water away from the bottom of the timber walls or the bricks at the base.  You could add a gutter along the roof edge to direct the water away, but also I would dig a gravel drain along the base, to minimise ground dampness and rain splashing back against the wall.

For an unheated garage, there is probably little to be gained by adding insulation, air flow is more important, so most of the time it will be at ambient temperatures anyway.

Apodemus

Ok, now I'm confused...  Your other thread suggests that all the outer work is now done?  Perhaps a web glitch and this thread only got added, when you posted the new one?

Glad to hear you've put gutters back!  

Section62

https://forums.moneysavingexpert.com/discussion/comment/79597167/#Comment_79597167

plumb1_2

Fix dpc material to the bottom to cover the timber and bricks
Fix breathable felt to wall
Clad wall in 300mm wide upvc panels/soffit boards ( choice of colours).
Maintenance free

or fit soft wood cladding and threat with preservative solution and paint every year

sujsuj

plumb1_2 said:

Fix dpc material to the bottom to cover the timber and bricks
Fix breathable felt to wall
Clad wall in 300mm wide upvc panels/soffit boards ( choice of colours).
Maintenance free

or fit soft wood cladding and threat with preservative solution and paint every year

I noticed there was roofing felt cut pieces were used for damp proof rather than items like this..
https://www.wickes.co.uk/NDC-Damp-Proof-Course-100mm-x-30m/p/133880

Which is better..?

Clad wall in 300mm wide upvc panels/soffit boards >> instead of external timber cladding..? If so I am replacing cladding only one side of garage, majority of other timber panels are good

sujsuj

Apodemus said:

Ok, now I'm confused...  Your other thread suggests that all the outer work is now done?  Perhaps a web glitch and this thread only got added, when you posted the new one?

Glad to hear you've put gutters back!  

Most of re-roofing with felt is done except edge panels and putting gutter. I though iys better do after fixing timber panels

sujsuj

Apodemus said:

Yes,  as Doozergirl says, you need to minimise the chances of the wood getting wet in the first place. it looks to me that you need to look at the water run-off from the roof first.  The eaves are not really deep enough to get the water away from the bottom of the timber walls or the bricks at the base.  You could add a gutter along the roof edge to direct the water away, but also I would dig a gravel drain along the base, to minimise ground dampness and rain splashing back against the wall.

For an unheated garage, there is probably little to be gained by adding insulation, air flow is more important, so most of the time it will be at ambient temperatures anyway.

to minimise water getting  closer, is it good to
(1) remove current brick layer and lay them again..? even getting new bricks from shop?
(2) have a a second brick row outside current one with some dpc layer between 2 brick rows..?
(3) plastering over outer brick layer
(4) Finally bitumen paint over over the outer brick row

All above needed /useful or just some..?

Definitely once gutter in place water will not fail from roof close to wall but wind will get water close anyway
Also on back side there can't be gutter .

sujsuj

Doozergirl said:

I would look at how a timber framed house is built, or even the Oakwood Self Build Garden Room group on facebook which works on similar theory.

Painting in bitumen is not a good idea. Wood needs to breathe and you're preventing it from doing so.   You are better with breather membrane wrapping the outside of your OSB/ply, then battens - one layer (or cross battens depending on the direction of your cladding) then cladding which you can treat.  

Wood isn't waterproof, there's no point trying to make it that way, by sticking waterproof things directly against it and hoping for the best, you just need to keep the water away from the main structure by not letting it get close.  

The other thing is that your floor slab is too low compared to the ground level.  You need at least 150mm from the bottom of your timber to ground level to prevent water ingress and splashback.    Dig around it to lower the ground levels.  Do not bring paving up to the structure, leave a gap, and ensure the direction drains away from the building.  

Most of log cabins don't touch floor, they are raised from floor.
Ok understood may putting bitumen pain allover cladding may not be a good idea. what about just last 2 layer wood that migh be coming to constant touch with water??

I may not be able to get surrounding level lower than the slab as back side is slightly raised above the brick level of garage. I thought about putting some soil to get that small cavity filled , but that may not be a good idea?

Apodemus

If the soil level at the back is above the bricks, then you need to dig that away and either leave a void exposed to the air or fill with gravel to form a "French drain".