Roofing advice with photos

[Pat Wilkinson]

My brother-in-law has a summer house/man cave that is like two buildings put together under one roof. It is made with T&G outside, and inside the thickest T&G I've ever seen. It was £18k, so the former owner said. It has been put on a dirt base, not concrete/flags etc. just dirt. It is probably 10 years old now and wasn't new when the previous house owner bought it.

Some of the bearers have rotted away and have now been replaced. The builder, who has been brilliant, has dug down all over the base of the summerhouse and packed Type 1 into the holes, filled with concrete and laid the bearers on to raise the floor off the saturated dirt as much as possible. It is far sturdier and feels solid to walk on with the new T&G chipboard floor, now here are the problems, the two buildings have dropped at both ends...

.... If you imagine a wooden summer house approx 20 foot wide x 12 deep with one roof across both buildings, the two sides are lower than the middle so it looks like it has pitched in the middle. Some of the rotten roofs around the edges have been replaced and re-felted but I have noticed (and I am just doing a bit of sanding etc.) that the walls at the top are pitching outwards. I hope the photos show this.
It is on all 4 walls and if you imagine it being 17 T&G boards high, the top board that the roof is attached to is leaning outwards. It may be historic so I have done some measurements and I will revisit these in a month to see if the measurements/lean have increased.

If you need any outside photos just ask, or any specific ones just ask. They have a small baby and I worry as the top board is leaning if it will collapse/and or is a safety issue. I did tell them to look at the roof first and the floor before doing any work but they chose to get on with it, have the floor done, new PVC windows and door and the inside all sanded and have plans to clad the outer wood with PVC to stop the rot getting worse. There are a few rotten boards on the outer skin that have been filled and wood hardener put on (I know!) They didn't want to go the expense of buying a new building but I did say that as it's on dirt the problems will come back eventually.

Would you please give me some advice after looking at the photos and if you need more just ask.

Thank you
on the external photos you can see the top rows leaning outwards probable 4 down from the top are all starting to lean. There's a talk today about whether or not to just do the small triangular part that's leaking at the mo, or do the entire roof. New OSB underneath and a blow-torched on felt to hot seal it to the wood.
Today, I also pulled down 3 pieces of the inside hardboard on the ceiling. I painted it yesterday and this morning there were evident signs that it leaked overnight as the hardboard was stained. And one final note, in each place I pulled the hardboard off there were signs of black mold on the wooden roof backing, quite a bit in fact and that worries me. They've a child who is nearly 2 and in and out of the summer house..

Can anyone look at the photos and tell me their opinion? Thank you

 

[Pat Wilkinson]

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[Pat Wilkinson]

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[Mr Chibs]

Morning

Looks like you've got a few things going on, from a quick glance at the picture library.

Looks like you've some rot at the bottom of the structure file ending 827.jpg

Looks to me like you might also have roof spread, which could be pushing out the top plank on the walls.
You have what is called a vaulted ceiling, so rather than having a triangle shape for your roof rafters, which gives a flat ceiling, you just have the rafters, these are more prone to spread, if not put together properly.

If it was me, as there are roof issues (water ingress) I would remove a couple of internal roof panels around the one with the paint off, and post the pictures so we can all have a look how good/bad it is. Is it actually hardboard panels or thicker.
Others will comment, but if the roof is salvageable, you might be able to replace the hardboard with OSB and stiffen the roof to stop anymore spread.

It won't fall down, but will require work to make it good, how work is unknown.

Keep us posted.

 

[Pat Wilkinson]

Thank you for the reply.

I was very worried it was going to fall down as the photos don't do the lean justice.
I am up there Tuesday so will tell you how far out the top plant is to the floor. On the right side, with the two windows, the lean starts from the 4th or 5th plank down. As it's double-skinned it is deceiving from the inside as it looks just like the top plank but the outside tells another story. Look at 915 & 921.

The inside roof is boarded with hardboard like you would see on the back of kitchen cabinets, they've been glued together with silicone. When I go there Tuesday I am meeting a roofer there so will take a few more boards down and photograph them. Every time we've exposed a board we've seen mold. It is warm up there though as there's polystyrene under the board for insulation, something they intend on removing as it isn't going to be used in Winter and in summer is painfully hot with it up there.

There have been numerous leaks historically, the builder has just replaced the first foot of the roof nearest to the guttering and re-felted in areas as the OSB had completely rotted. This week we've had 2 leaks already and haven't got into the bad weather yet. He either keeps Whack a mole with the leaks or bites the bullet, has it all reboarded and re-felted with the roll felt as opposed to shingle, due to the cost.
Would they hot seal the felt dow, do you think?

Again, thanks for the reply and I will post some more photos Tuesday.
Thank you

 

[Pat Wilkinson]

Roof was stripped today, with definite spreading and mold ingress. Literally, hundreds of nail holes all the way through the hardboard, some screws too. It is all coming off, all being reboarded and hot felted down. I think he's had enough now.