Flat roof

Mistral001

Lorian said:

I think you will need building control approval and may need to improve the insulation to current standards too depending what's there already.

https://www.planningportal.co.uk/permission/common-projects/roof/building-regulations-work-to-an-existing-roof

Fibreglass may increase the noise when it rains. Resitrix Reinforced EDPM is good but not the cheapest.

This is a good link.   It is quite unusual to require Building Control Aproval for recovering a flat roof.  The weight of the roof covering if it is more than 15% heavier than the original catches some people out, but unless you go for someting like butyl rubber and gravel this is unlikely to apply.  However in this case the rule regarding more than 25% of the total builing envelope might apply here if the bungalow was a very small one.

FreeBear

Mistral001 said:

Lorian said:

I think you will need building control approval and may need to improve the insulation to current standards too depending what's there already.

https://www.planningportal.co.uk/permission/common-projects/roof/building-regulations-work-to-an-existing-roof

Fibreglass may increase the noise when it rains. Resitrix Reinforced EDPM is good but not the cheapest.

This is a good link.   It is quite unusual to require Building Control Aproval for recovering a flat roof.  The weight of the roof covering if it is more than 15% heavier than the original catches some people out, but unless you go for someting like butyl rubber and gravel this is unlikely to apply.  However in this case the rule regarding more than 25% of the total builing envelope might apply here if the bungalow was a very small one.

The 25% rule applies to each thermal element. So even if the flat roof only accounts for 15% of the total roof area, strip more than 25% of it (the flat roof), building regs apply.

SaintAlf

Thanks for all the responses...one of the quotes is for a PVC membrane, no one mentioned that, any views?

Mistral001

PVC has been used on industrial and commercial flat roofs for years.  I first saw it (Trocal) used on a shopping centre over 40 years ago.  It is a high quality product with durability.  Needs well trained people to install it, so expect to pay a premium for it. 

badmemory

My flat roof is rubber.  A little more than felt but guaranteed for 20 years not 10.  I was told it should easily last 30 & unlike the felt roof have seen no reason to doubt it.

Phil4432

Doozergirl said:

SaintAlf said:

Thanks for your responses, any thoughts re the typical cost for that 6m x 4m area, and finding someone to do the work?  It's a bungalow so easy to get to the roof.

The insurers say they have no requirements for the inspection other than "someone who's job is a roofer/builder"...

What's the specification?  Are you getting full quotes with a breakdown?  They could be just intending to replace rhe covering, but what is your insulation situation? If it hasn't been maintained and has leaks then are they replacing the boards and joists, accounting for the potential rot? 

Use someone registered with a trade association like the https://www.nfrc.co.uk/ specifically for roofers or www.fmb.org.uk for wider scope.  

Its actually likely that some of the joits will need partial replacement if the roof has been sodden for sometime.  This happened to me, wasn't a dramatic increase in price.  Boards are actually more likely to need replacing than joists, easier and less expensive.

Someone mentioned planning permission; if you are simply replacing a flat roof like for like, that shouldn't need any permission but its worth checking if in doubt.

My extention and garage was one storey high, no need for scaffolding. 

https://www.corc.co.uk/

FreeBear

Phil4432 said: Someone mentioned planning permission; if you are simply replacing a flat roof like for like, that shouldn't need any permission but its worth checking if in doubt.

Like for like repairs never need planning permission (extensive repairs on a listed building may require Listed Building Consent though). Stripping more than 25% of a flat roof triggers Building Control involvement, but that is not the same as planning permission.

SaintAlf

Thanks @Phil4432 and @FreeBear for those comments about planning permission, very helpful.