Exposed purlin end under overhanging eaves - rot?

[chaoticj]

Hi,

So the front, side and rear of my house has exposed purlins under overhanging eaves.

At the front, the purlins on the left hand side of the apex towards the top and middle of the roof have a lot of paint missing - I just assumed they had weathered and needed painting but they seem on their 'top' side to be down to the bare wood.

They are 8 x 4 and set at a 45 degree angle. They may have some kind of rot? looks like they have cracks and the higher up one seems to have a hole where it meets the soffit.

I've gone into the fully insulated attic space and jabbed the worst looking one with a screwdriver - it's solid. There is a cavity wall which is about 400mm thick.

I can't see anything amiss up there, some powdery spots on areas of timbers which come off if I wipe them with my finger, but no kind of bad smell. I've looked down the rafters as well - there's a piece of insulation board sitting between each of them.

Does anyone know what this could be, how it could have happened and how I can get it fixed please?

We have been here about 4 years, the purlins have been like this a while - not sure how long. The slate roof has vents dotted around it - there's a decent breeze up there. It's laid with impermeable felt also. It looks like there may have been some difficulties in the past as some of the original planked soffits look to have gone a bit rotten - but nothing recent? We lost some slates etc. on the opposite side of the apex but had this repaired.

Many thanks,
chaoticj

 

[blup]

Looks like they should be repairable, probably the result of water ingress from an old unmaintained gutter or soffit, dripping over many years.

They don't seem to be purlins in the technical sense as they appear to fit under the end rafter only.

Blup

 

[chaoticj]

Thanks @blup I'm guessing it'll be a scaffold tower jobby? which trade would be best for this? Roofer, builder, painter? I'm not really sure.

I think they are purlins? They support the eaves/roof overhang, the one at the top goes through the space at the top of the house, back to load bearing wall at the back of what is the front 2nd floor bedroom, it's bare wood, the lower down one is the same but you can see it in the front 2nd floor bedroom and it's painted or covered in some sort of paper.

So the section of roof above the front 2nd floor bedroom rests on these. The red lines in the picture are where they roughly run at a 45 degree angle.

The tradesperson working on the house thought it was dry rot.

What's weird is where has all the paint gone? I don't remember finding any flakes of paint on the ground? You can see the layers of black, blue underneath that and even green! that must surely be the original Victorian paint.

 

[blup]

I can see now they run further back than i thought. You will have to examine and remove the rotten wood before deciding what to do, you might get away with 2 part epoxy wood filler, or alternatively need to splice in new wood.

Not really a roofers job and too small for many builders, maybe a chippie with a head for heights.

Blup

 

[catlad]

Small tin of black bitumen paint will sort that out.

 

[datarebal]

I've seen them totally hollowed by rot from the ground they look ok until you look close

 

[tell80]

OP,
Can you post better defined pics for the purlins on the out side, and the soffit above them - and clear focus pics showing the purlins inside the loft? Will you ID each pic?

If you have rotted out purlin ends with the rot going back through the wall then eventually, if not now, you will have support difficulties for the wide verge soffit, barge board and roofing above.

From your balcony, a long batten of timber with a spike fixed to the end will allow you to probe the outside purlins.

 

[Coopa]

Hi the last time I encountered this ,a builder came and cut the bricks to the side of the rotten purlin ends to rough size of new purlins and run through into loft alongside purlinswith a 6x2s or something the same size as original , into same position as the original on outside , ran it from the front edge to about 6 foot ‘ into loft and bolted them to original purlins which inside were sound . Once the verge weight was being held he cut back rot purlins to good wood and painted the cut end in preserver or something like that . He then bricked and cemented the holes left by the removed rotten purlins .

 

[Coopa]

Also the rot was caused by faulty lead work around his chimneys and water was getting through and soaking in

 

[chaoticj]

Hi,

Sorry it's taken so long. Having had a good look in both loft spaces and 'rooms in roof', I am fairly hopeful the rot is contained to the outside. It's not possible to see all the beams from the inside - and definitely can't see any of the wallplates.

I contacted some joiners/carpenters - some only do kitchens etc. another would only look if I obtain a structural engineers report.
I can't get a structural engineers report as there is no scaffolding to access the front left hand side.

Got a typical no show and ghosted, another looked whilst I was out but says it's too high to assess on ladders and the existing scaffolding is too high as well - doesn't seem keen.

I've had 2 prices each is around £3K and could be more depending on the extent of rot and materials used.

Quote 1 it will take 2 men around 2 weeks, the front will be scaffolded (at my extra cost - £300), the side and rear they will do it off a ladder footed by the 2nd man. The purlins will be sanded and repaired using resin at £50 a tube then painted with a solvent based paint. Says the front 2 are just weathered and the wall plates have been clad in interior grade ply which has gone rotten. Materials £500+ labour £2500.

Quote 2 it will take 1 man? 6 days (3 phases - 2 days per apex), the front, side and rear apexes will be scaffolded - over 50% of the total cost is scaffolding. The fasica, soffits and purlins will be prepped. The purlins repaired using 2 part filler or spliced. Everything will be painted with water based Sadolin Superdec paint which typically lasts 10 years.

It's £1600 for scaffolding (front - £550, side £600 and rear £450) or £1850 for a complete wrap around.

I think it makes sense to paint everything due to the scaffolding cost.

I'm in a bit of a quandry now as I'd booked in for all new gutters and downpipes to the main house, that company was going to put their own scaffolding up - over the single storey extension and a tower to reach a rotten wooden gutter between the side and rear apexes. Their price apparently includes £300 for that. If I had the wraparound and they knocked £300 off there wouldn't be any difference in price.

There's probably a few other things that it might make sense to do or that I'd like doing - I hadn't planned on having nearly the whole house scaffolded.

I've labelled @tell80 these pictures of the apexes and wallplates/purlins:

Front



F1, F2, F3, F4, F5, F6 (can't get F7 as scaffolding in way)
I think F1 has some rot/weathering where it meets the fascia
We already know F2 and particularly F3 are weathered and have some rot from the original pictures

 

[chaoticj]

Side



S1, S2, S3, S4, S5
It's hard to tell, I think S1 could be hiding something, S5 looks a bit rotten where it meets the fascia

 

[chaoticj]

Rear


R1, R2, R3, R4, R5, R6, R7
I think R1 looks like the worst of the lot. How can this just be clad with the wrong plywood?

There used to be a chimney stack at the top in the middle, what you see on the outside R4 is sat on the top of what is left of the chimney and a larger beam is butted up next to it.

I think R7 has some rot where it meets the fascia.

 

[catlad]

Still struggling to see much wrong in those pictures.

 

[chaoticj]

What would you use to fill some light/moderate rot? and what wood to splice?

One tradie says epoxy (I think its called Timbabuild) which seems suitable.
Another says two part filler (like car body filler) which it says online could flex and come out after a couple of years?

For splicing one says Iroko/hardwood and the other pressure treated wood like a fence post?

Also paint, Sadolin Superdec lasts 10 years, but Zinsser AllCoat says 'up to' 15 years?
Gloss looks nicer than Satin..

I'm told solvent based lasts longer.. but water based might be better for the wood?
Seems like a lot of contradictions.. but anything is better than bare rotten wood I guess.

 

[DiyNutJob]

Why not use both paints and see which works better? Claims are just that: claims. Zinsser seems too good to be true. It doesn't need priming, it can be recoated after 1 hour, and lasts 15 years. In effect, it's a miracle paint. I am surprised it doesn't do your house chores for you, and tuck you in bed with a kiss. Not saying miracle can't happen, but back in the real world, oil based is a known quantity and withstood the test of time. I have seen a 10 year paint lasting 10 years or more. That's pretty good going. Although not all 10 years paints are the same. I am not quite impressed with sandtex, but I am willing to give it more time.