Patio roof gutter issue in property we have offered on

FreeBear

Obeone said:

We just discovered the surveyors photo actually shows the problem is even worse. They thought the downpipe for the rest of the roof was in the way so they have redirected it onto this roof too. That's a huge flow of water going into the wall. Does this change any of the advice above?

No flashing between the "roof" and the walls - Even if you got the gutter sorted, water will still soak the wall... With the downpipe dumping water water from the roof, I suspect you'd want deep flow guttering on the polycarbonate roof.

So the bill for fixing the bodges has gone from £2 for just an end stop to £300-500 for lead flashing, deep flow guttering, and downpipe. Add another £500 if you need a soakaway. Oh, and you won't be able to work on top of that polycarbonate roof to put flashing in. Scaffolding will be needed, so another £500....

Knock it down, reinstate the original downpipe, and think about doing it properly once you've settled in.

Eldi_Dos

It would be advisable to check if NHBC warranty is valid after that unlikely alteration.

Obeone

Thank you, would you now be concerned more about degraded wall insulation, foundation issues and later issues with mould and damp being transfered through even after the roof removal. Given the volumes of water involved?

TELLIT01

Presumably, the drain the rainwater pipe previously fed into is now concreted over under the patio?  I stick with my previous advice but upgrade it to run away not walk away.

stuart45

Do you know if it's a timber frame house, or traditional brick/block csvity?

Obeone

The surveyor report said the walls are:
"The external walls are of cavity masonry construction (comprising two leaves of brickwork/blockwork separatedby an air gap)."

stuart45

Modern cavity walls are pretty good at protecting the insulation and inner skin from moisture. There's a number of methods of building a modern cavity wall, but there is often a 2 inch air gap between the outer skin and the insulation. Even with full fill insulation boards, their method of construction protects them.