New extension roof

[chickenlips]

I thought about a flat top slice, but it would need the most structural works and be the most technically challenging to build correctly and detail. It would probably be a last resort.

From a build perspective, a flat roof section wouldnt be that difficult if the roof was designed in trusses. Mono Flat tops running into the existing with a little make up on the hips etc. Fairly simple in all honesty, the only difficult part would be getting the planes to match through.
Probably would be cheaper to put up as well.

 

[Peter1919]

The plans show a small roof after the first floor thus stepping the first floor extension wall back and allowing the roof to match in with the original roof better. No idea how it was intended for this to be built mind given it would need some way of supporting the upper wall.

However given that is what the approved plans show then if it has been built differently it is probably in breach of its planning permission

 

[^woody^]

From a build perspective, a flat roof section wouldnt be that difficult if the roof was designed in trusses. Mono Flat tops running into the existing with a little make up on the hips etc. Fairly simple in all honesty, the only difficult part would be getting the planes to match through.
Probably would be cheaper to put up as well.

It would not be easier for the OP, and then there is the ridge detailing problems where the flat meets the pitch

Its the least prefered because it is more challenging to construct, there is more to go wrong and more to maintain = higher risk

 

[chickenlips]

From a build perspective, a flat roof section wouldnt be that difficult if the roof was designed in trusses. Mono Flat tops running into the existing with a little make up on the hips etc. Fairly simple in all honesty, the only difficult part would be getting the planes to match through.
Probably would be cheaper to put up as well.

It would not be easier for the OP, and then there is the ridge detailing problems where the flat meets the pitch

Its the least prefered because it is more challenging to construct, there is more to go wrong and more to maintain = higher risk

I cant comment on the detailing part, as i only design roofs/floors.

But from a roof perspective, I know I could quite easily design a flat topped roof that would be very simple to fit on site. The only cut in work would be the loose rafters/ceiling joists on the hip corners. Maybe a little work on the valley onto climbing onto the existing roof however most of that could be done in flat topped diminishing trusses.

We get a lot of badly drawn 'matching in' roofs where when we get to site, we find ourselves almost redesigning the roof due to 'Techinical draughtsmen' not experienced enough to envisage how the roof should match into the existing.

 

[Jsmithy]

The plans show a small roof after the first floor thus stepping the first floor extension wall back and allowing the roof to match in with the original roof better. No idea how it was intended for this to be built mind given it would need some way of supporting the upper wall.

However given that is what the approved plans show then if it has been built differently it is probably in breach of its planning permission

I've stepped it back. The upper floor is 500 less than the lower.

 

[Jsmithy]

What is the roof pitch on the main house?

Just back on today woody ,
Not sure of pitch ill find out and post tomorrow.

 

[Jsmithy]

The pitch pf my main roof is 10 in 12 which is 40 degrees
cheers.