Which plasterboard?

[Donquick]

Hi all,

Bit confused about the way forward with my timber frame extension. I am just ready to plasterbord and i need to clarify whether i need to use the foil backed board for the ceilings between the internal floors or not. I know i need the foil for all the boards on the external walls, but i don't know about between floors. Also i have a single storey flat roof, should the ceiling of that have the foil boards too?

As a supplementary, should i bother with 9mm board on the ceilings and 12.5 on the walls or should i just make life simple and go for 12.5 all over. I guess the thicker boards are better for insulation.

Thanks in advance for any tips!

 

[Richard C]

Bit confused about the way forward with my timber frame extension. I am just ready to plasterbord and i need to clarify whether i need to use the foil backed board for the ceilings between the internal floors or not.

No.

I know i need the foil for all the boards on the external walls,

What else have you got in there; insulation, damp membrane?

Also i have a single storey flat roof, should the ceiling of that have the foil boards too?

For the little additional cost involved, yes.

As a supplementary, should i bother with 9mm board on the ceilings and 12.5 on the walls or should i just make life simple and go for 12.5 all over. I guess the thicker boards are better for insulation.

Use 12.5mm boards virtually nobody uses 9.5mm for ceilings anymore.

Is this extension being done in accordance with Building Regulations? Have you submitted a Building Notice? Have you had any inspections?

 

[Donquick]

Hi Richard,

No.

Thanks, but will it matter if i do use use the foil on the ceilings?

What else have you got in there; insulation, damp membrane?

I have got celotex insulation up to spec. (and over spec in some areas) I was going to put a membrane, but the BC guy said not to bother and that i should use foil back board as it is considered a better solution. He would be happy with either one or the other he says.

For the little additional cost involved, yes.

Again, thanks - will do.

Use 12.5mm boards virtually nobody uses 9.5mm for ceilings anymore.

Again, thanks - will do.

Is this extension being done in accordance with Building Regulations? Have you submitted a Building Notice? Have you had any inspections?

I am a bit maverick with what i will attempt at times, but the answers are yes, no and yes to those questions - i do want to sell the place one day after all

I had my last inspection a couple of weeks ago, and i forgot to ask about the plaster board on that occasion. The problem is that i am using the BC guy, who is extremely helpful, to fill in my knowledge gaps when i see him. I try to ask everything i need to know for the next phase when he visits, rather than blatantly phoning him to ask a question. Hence, i thought i would ask this question on the forum and leave him a while until my next set of questions

Thanks for your help.

 

[Richard C]

but will it matter if i do use use the foil on the ceilings?

No it won’t matter.

I have got celotex insulation up to spec. (and over spec in some areas) I was going to put a membrane, but the BC guy said not to bother and that i should use foil back board as it is considered a better solution. He would be happy with either one or the other he says.

Personally I think I’d prefer a properly taped & sealed membrane over foil back boards but if you’re BI is happy with Duplex.

I am a bit maverick with what i will attempt at times, but the answers are yes, no and yes to those questions - i do want to sell the place one day after all I had my last inspection a couple of weeks ago, and i forgot to ask about the plaster board on that occasion.

I’m a little confused how can you can be having BI inspections if you’ve not submitted a building notice . It’s important that you have all the necessary inspections & get a completion certificate for the extension from your LABC or it will cause problems later & could affect the saleability of the property.

 

[Donquick]

Hi Richrd,

Thanks again for the thorough answers about the plasterboard situation, appreciate it. I assume you mean taped and sealed membrane under foil back board. I may well go for this option to double up as you suggest - that was my original intention admittedly.

I don't know much about the building control situation as this is my first such experinece, but it seems like we are going to have this conversation whether i like it or not

As far as i am concerned i am doing it by the book, but i am happy to take your advice.

as far as i know, I got planning permission and i then approached the LABC and did what they asked me to.

They told me that i could either have a fully specified project drawn up by an architect and just build it and that would be the quick and trouble free route OR i could get inspections incrementally during the build and each part of the process would be signed off as we go (i believe the latter was a little more expensive).

I chose the second option because there was a fair bit of learning as i went along and i didn't have an architect so i couldn't do the full spec prior to commencement.

So far the guy has come round about 4 times and on each occasion he has said that he has been very pleased with the work and that he will sign off various aspects of the build. On each occasion i have asked him at which point i should invite him back and i have done so.

Assuming he is who he says he is and he isn't going to get to the end and say 'ha ha April fool' I hope i am going to be ok. Maybe i am getting mixed up with the terminology and i do have a building notice, but i thought that was the option that i didn't select with the fully specified drawings. As i say i am not an expert, but they seem to be happy with what is happening. However, I will check to make sure i'm not going to have problems at the end.

Thanks again.

 

[Richard C]

A full plans submission is the first method you describe but since you did not follow this route, you must be doing it under Building Notice. You (or someone on your behalf) must have filled out a submission form & you must have paid a fee which would have been based on the value of the work being done. So far it doesn’t sound like you will have any problems!