Red Cedar Cladding

Furts

Your new photo came through whilst I was posting. The gist remains similar - the door and window frame should be taller, or the cladding visible to the right should extend above the door and window. Equally the soffit should stop short of the window.It is clear the contractors have run the soffit through probably not knowing about, or not caring about, where the frames were to be located.


To any competent builder the detail looks so poor I am amazed it got through the two year NHBC Initial Guarantee Period. (It should not have got past snagging, but here we have to accept commercial realities, or commercial cynicism)

missile

Thanks for your comments, please be advised:

Furts wrote: »

Various points here. Only you know the wall construction but the external exposed soffit should not be running through to your living area. For example on a cavity wall house it sits on, or extends onto, the face brickwork and not the internal leaf. The water ingress is into the cavity.

Above you window should be an impervious rain screen, There is a damp proof membrane with a drip detail over sailing the head of the pvcu frame. This could be achieved with upvc cladding. Not usual to fit upvc drip trim above a rebated pvc window. The vertical timber detail is a built in defect just waiting to give water ingress. Bluntly it should never have been built - there are too many flaws with it.

The broader issue is how the apartment was built. It is likely the window has been set too low and it was never intended to have an infill detail above the window. It has been built to architects design A similar argument would be the window was manufactured too small. Assuming all details were thought out this is less likely - with spec build everything is pre ordered so the opening should be suitable to receive the window.


Why the situation has arisen is history. A savvy buyer would have checked matters out long ago so this too is history.


It does seem absurd that matters went to a surveyor, and to NHBC and still are giving problems. Harsh as it sounds OP has to ask searching questions on why this situation has been allowed to happen. Not sure what you mean? One buys a house from a reputable builder and does not expect it to leak.

Jackmydad

I know a chap from another forum I go on, who does high quality site joinery and carpentry.
He says they are always having to sort out this type of thing from the architect's plans.
With that angled soffit I can't really see how it can be made "waterproof" while the soffit runs back beyond the vertical detail.
It's just a thought, but supposing the membrane used behind the soffit cladding comes back round to the front above the window, running down behind the vertical detail, then the plastic beading fitted above the window isn't blocking it from draining in some way?

missile

Jackmydad wrote: »

I know a chap from another forum I go on, who does high quality site joinery and carpentry.
He says they are always having to sort out this type of thing from the architect's plans.
With that angled soffit I can't really see how it can be made "waterproof" while the soffit runs back beyond the vertical detail. If he thought about it at all(?), perhaps the architect consider the overhang would prevent rain water reaching this joint.?
It's just a thought, but supposing the membrane used behind the soffit cladding comes back round to the front above the window, running down behind the vertical detail, then the plastic beading fitted above the window isn't blocking it from draining in some way?

I think you have a valid point. I was thinking this too. As posted before, I had a crazy(?) idea to drill a hole to let the cavity drain

teneighty

I'll have one more attempt.

This is bigger than just the detail above the door, the water is penetrating the roof/canopy and running along the top of the sloping soffit boards as per photos in post #11

This will probably involve extensive work on the roof and soffit and cladding above the door. I assume OP is a leaseholder so he should not be messing about with the building elements which he does not own. I'm sure the freeholder would be delighted having failed to get the original builder/NHBC to accept responsibility to pass the blame on to one of the leaseholders who has cut into cladding/soffit to try an install a drip detail which wont work.

Jackmydad

teneighty has very valid points.
Is the OP sure that it's actually "his" problem?
It looks as if it could be a design fault, and if it is could mean a lot of work.

Whatever, I wouldn't go drilling holes. Liable to make it worse rather than better!

missile

Thanks to all for your valued comments. You have given me much to ponder over.

tony6403

leveller2911 wrote: »

With regards to the vertical boards The reason you are getting water ingress above the door frame is all the moisture is soaking into the cedar cladding ,running down the through the timber cells and seeps out the bottom and this is then tracking back along the door frame till it reaches the gyproc which then becomes wet...
.

Interested as to evidence for this conclusion?
Cedar is particularly good for cladding as it contains oily compounds which provide a natural block to moisture and decay.
Its properties are such that there is no need to treat it.
I have experience of using it and have never come across this.

leveller2911

tony6403 wrote: »

Interested as to evidence for this conclusion?
Cedar is particularly good for cladding as it contains oily compounds which provide a natural block to moisture and decay.
Its properties are such that there is no need to treat it.
I have experience of using it and have never come across this.

Western Red Ceder which is what the OP has asked about does indeed contail natural oils and is very durable and doesn't need treating but the oils don't prevent moisture from being absorbed.

However the cell structure of WRC is unique in that it will soak up water very, very quickly but retain its shape and dimensions. It loses water/moisture very quickly and even after its been planed/moulded it will keep its shape and dimensions. You couldn't use any other timber in the same way for making joinery or cladding foir that matter. If you tried to run out cladding/joinery from Douglas fir that has a moisture content of 25% it would split/shrink and fall apart. WRC can have a moisture content of 90% when delivered and you can still plane/mould,mortice,glue it together within a couple of days.

You couldn't make windows and doors for a house with WRC because its cell structure allows moisture to be absorbed continually. There are other species of Cedar that we use for windows/doors etc such as Brazilian Cedar. This needs to be kiln dried to be used for Joinery but again is very stable. Only downside is its very soft and can easily be damaged and it needs to be sealed/painted/stained.When people treat WRC its purely down to keeping the natural colour or giving it a colour and not for the purposes of making it more durable.

Below is just one of the sources available online:

Dimensional Stability

Like all woods, Western Red Cedar is hygroscopic and will absorb or discharge moisture to attain equilibrium with the surrounding atmosphere. However, it has a very low shrinkage factor and is superior to all other coniferous woods in its resistance to warping, twisting and checking.
Shrinkage of Western Red Cedar
Radial shrinkage applies to the width of vertical grain (quarter sawn) timber.
Tangential to the width of flat grain (back sawn) timber.

Direction of Shrinkage

Shrinkage in Percentage

From green (25% or greater moisture content) to:

From kiln dried (15% average moisture content) to:

15%

12%

6%

15%

12%

6%

Radial

0.96

1.2

1.8

0

0.3

1.0

Tangential

2.0

2.6

3.8

0

0.7

2.1

Western Red Cedar is rated amongst the highest of softwood species for stability.



http://www.timbeck.com.au/specie-properties/western-red-cedar/properties#stability

missile

Hi,

When people treat WRC its purely down to keeping the natural colour or giving it a colour and not for the purposes of making it more durable.

What product would you recommend?