Replacing lean to polycarbonate roof with solid roof

[Michaelsf90]

This may be a lengthy post but I'm hoping for some advice and understanding before I decide what we are going to do. We have a small extension on the side of the house. A lean to which we use as a utility room. With the roof being polycarbonate it's freezing in winter and boiling in summer. The extension is all brick built and then the polycarbonate roof on top

Now I plan on having the roof replaced. Framed out, insulated, two velux windows and quite possibly lightweight roof tiles. I have a guy coming to look on Saturday. I know I can ask him hut I'm hoping someone on here can offer me some insight before the guy comes

With it being a polycarbonate roof I'm under the assumption it was built without planning permission. In fact when we bought the house nothing come up on any searches about that extension. So where do I stand with regards to having the roof done. Will I need a structural survey or foundations checking. I want the job doing to be able to use the room better but could it open a massive can of worms?

 

[cdbe]

Probably doesn't need planning - Google permitted development. Also probably doesn't need building regs - provide it's separated from the main house by an external quality door and isn't heated by the main house heating system. Re-roofing won't affect this. But obviously you will want it done to a reasonable standard - suitably sized rafters, tiles and velux suitable for pitch etc.

 

[Michaelsf90]

It is separated by a wooden door which was the outside side door. So it is more of an external door. But it is heated by a radiator connected to the rest of the house. I haven't done any of this work. We moved in and inherited it. That was 5 years ago. Nothing come up on surveys and nothing on the checks. It will be a proper job done I just don't want to create any problems but also don't want to cut any corners with building regs and get my fingers burnt. Also the building is built up to the boundary. So it acts as the fence between us and next door

 

[cdbe]

You need to make the rad independently controllable from the rest of the heating system. Usually done by fitted a wireless/smart TRV.

 

[Michaelsf90]

Good idea to fit the new smart trvs. I've just turned the lockshield valves right down so it doesn't absolutely blast all the heat out and lose loads of heat

 

[fandyman]

Hi @Michaelsf90 How did it all go in the end?

I am in the process of doing very similar job with installing a solid roof over and old conservatory and a few ppl told me I would need building regs to have the solid lightweight roof installed. That would then in turn open a potential can of worms for me as I have also a radiator inside the conservatory connected to the main house central heating (albeit it has a TRV and nonetheless was told the new regs say explicitly that the source of heat cannot be coming from the main house so I am left with removing the rad and installing electric one instead) and no thermal separation as doors were removed by previous owner. The foundation are also 450mm only so not sure about the roof re building regs and builders tell me it will just be fine - do not worry mate

I am just at the point whether I should rebuild the connie from scratch or completely demolish and close off with external doors in the place of the opening...

 

[Michaelsf90]

I never had it done. The builder came to do it. He was gonna just put a proper solid tiled roof on. But he needed access from the neighbours side as it goes up to the boundary and leans that way and the neighbours refused. So the job stopped. I could have legally requested access but I couldn't be bothered.

Il not forget. Wel probably move in the next 5 years or so just hope it holds out until then.

How come your thinking of knocking it down if builders are satisfied with installing the lightweight roof. I know some lightweight roofs are like accredited and approved so no need for building regs. I find you tend to get penalised in life if you want to do things properly.

 

[fandyman]

@Michaelsf90 Shame it did not work out for you and I am sure it will hold out until then!

Interesting approach with your last sentence - I am finding it out too from time to time myself as well

Yes I am aware about the accredited and approved but when I called the council they told me they would still need to inspect it (it does not make sense right?). Maybe the reason is they went bankrupt recently and are desperately trying to make any sort of money however they can...

I am also worried that the builder told me there is no need to check foundations although the roof still carries some weight correct (even though it is lightweight tiled roof)? Maybe I am overthinking but I've just been off a call with SE and he would have to check the state of the foundations to tell me so it is not enough that they are 450mm it seems even for a lightweight tiled roof.

Are they all trying to make money out of me or the regulations changed recently indeed?

 

[conny]

If any structure is built up to the boundary, you have to be aware that, any rainwater pipework, (gutters, downpipes etc), cannot cross that boundary, even by 1"

 

[fandyman]

conny Sorry my connie is not next to a boundary. It is a detached house and there is plenty of space each side to next neighbours.

The question is purely re the accredited and approved roof in relation to building control as I am planning on replacing polycarbonate roof with a solid lightweight one. I think that solid roofs do still need inspection to be approved. This can be either done by the local council or by private approved inspectors companies but it will still require someone to sign it off. Am I right?

I am trying to avoid a situation where I let the builder build the roof over the 450mm foundation and dwarf wall and then BR inspector rejecting it later for incorrect foundations etc. The builder is trying to convince me I do not need an inspector verifying it at all as it is pre-approved.

He thinks foundations are allright and I also do not need anyone checking them upfront which makes me question his approach... but maybe I am wrong?

 

[Michaelsf90]

Maybe speak to a structural surveyor first? Get some advice. I know not all may be very helpful. I spoke to one chap who was great. They should know if these pre-approved tiled roofs will be suitable for the foundations you have. I know it's opening a can of worms tho and feels like it can be more hassle than it's worth. Would you be willing to knock it down and start again?

I made the assumption that a lightweight roof must weight the same as a polycarbonate or glass one.

I'm sort of glad we didn't get ours done considering. I checked the foundations and they were around 800mm deep but not particularly thick. I just stuck this film on the inside of the polycarbonate. It's solar reflecting so it won't get as baking hot.

As for the guttering the guttering is the boundary. So they built up to the fence. The guttering sits in line where the fence would be. Personally I feel it takes a special kind of idiot to stop a neighbour from having work done on a lean to side extension that was there when we moved in and was there when they moved on. For all they know it could be leaking. And to say no we can't do it because my 10 year old son threw a can of pop into their garden because the woman keeps telling him off because he occasionally throws a tennis ball over when playing with the dog is pathetic. And what's worse is they phoned the police about that. And the police turned up! Which is why I'm glad we saved the thousands the roof would cost because once markets and the economy settles wel be off.

@fandyman Do you have a trade by the way? Or just general diy enthusiast?

 

[fandyman]

@Michaelsf90 Thanks for your post.

I've talked to SE and he thinks there is no building regs required for a warm roof if part of conservatory apparently but it is very opinionated and depends who you talk to. How come it is so unregulated I am thinking? He said he would have to check with a colleague at council's building control department but he is fairly certain it is not required.

I made a call to building control and was told that if the doors are there and there is no central heating connected to the main house what I install as a new roof does not matter to them. It is just a conservatory then and exempt from regs. I can apparently install anything at my own risk?

I wonder why there is so much talk then from those warm roof companies of building regs accreditation and approval. Maybe it is just a selling tactic to attract more customer even though it is not needed or maybe the building regs is required for conservatories installed in new buildings and if it is a repair work (even though it is not like for like - i.e. polycarb replaced with solid roof) it is not needed?

The SE still confirmed 450mm foundation would not be enough for a solid warm roof (unless the foundations are directly on chalk for instance). I have now dug trial hole and checked the foundations of the house are 400mm (built in 50s) and the conservatory foundations are same depth at 400m. He thought this would not be enough for a solid roof from build regs side but he said I can build whatever I want as it is an extension? All the builders are telling me this will be enough and they give 10 year warranty it won't sink. I am at crossroads really...

 

[fandyman]

He thought this would not be enough for a solid roof from build regs side but he said I can build whatever I want as it is an extension?

I meant to say he said I could build whatever i want as it is NOT an extension of course.

 

[Michaelsf90]

I know building control also check other things. Insulation levels. Ventilation. Mine has cavity wall insulation and the roof would have been insulated to standard. For me it was just the foundations. It is incredibly frustrating. It's a minefield of legislation.

I'm an electrician by trade but in terms of building, especially domestic and the requirements I don't know a right lot. It's crazy the house foundations are that deep. I'm assuming it's two storey. All that weight and its fine. I suppose its what your comfortable with. Either put external doors on so you can shut it off. I wouldn't remove the radiator. We just have ours turned down on the lockshields. So it heats enough to take an edge off but isn't wasting tons of heat. That way you can shut it off from the rest of the house in winter. The solar reflective film, ooolkote I think it's called, has made a huge difference when it's warm. So now it isn't like a furnace in summer.

I'd imagine with a lightweight roof it will be fine. All roofs and structures are designed with the added weight of snow in mind. I can't imagine a lightweight roof having much weight. Does it pitch like a lean to roof or is pitched on several sides that meet in the middle?

 

[fandyman]

It is pitched on several sides that meet in the middle yes (the roof ridge runs parallel to the back wall) so I think it is then called a hipped back roof. It was constructed this way due to a soil pipe which runs along the back wall from the first floor bathroom connecting with a stack next to the connie. I am fairly confident the foundations under the connie are going to be enough (since the same size foundations are under the house).

I think we will bite the bullet and decide on a warm roof. It would be a shame to lose this space and currently the doors, windows and roof are in a terrible state and generally on their last legs. We were hoping we could install a victorian gable roof but the soil pipe would have to go through the roof which would not look nice from outside hence we are going to install same hipped back structure I suppose.

We will be putting external doors too and the radiator lockshields is an option for now although I was told this would not pass building regs when we come to sell the property - it has to be separately connected (not to the main house piping) or different source like electric heater. We would still keep the house connected radiator and just remove it and cap the piping under the floor when we come to sell.

I suspect there would be some insulation in the dwarf wall and floor (floor has underfloor heating so I assume there must be some insulation underneath unless it was done by some cowboy which are plenty).

We were debating on the solid roof versus demolish it completely and just install external doors in the opening as the costs to rebuild the windows, doors and warm roof are coming in the range of 20-30k in this part of the country. It is a bit steep for just a connie but I guess losing that space (about 12m2) would hurt us more. We are really hoping the warm roof and new glazing will make it warm enough to be able to use it all year round although we may be day dreaming really. It's anybody's guess judging from people's feedback we got as it is case by case and the orientation/shading etc related.