Making loft conversion quiet and cool: soundcheck plasterboard, triple-glazed velux?

zoothornrollo_2

Work is due to start on my loft conversion in a few weeks' time and I am thinking of what I can do to make it as comfortable a space as possible.
I'd like to keep it cool in summer and I'd like to try block out plane noise as much as is practical / affordable.
So I was going to go for triple-glazed velux on the basis that this will help keep the room cool in summer (it is a south-facing roof slope) and hopefully also block some noise?
Would triple glazing the dormer windows (north facing) make much extra difference sound and temperature wise?
I am also thinking of soundcheck plasterboard as we do get quite a bit of plane noise: is this stuff effective and worth the extra expense?
Can it go in the roof as well as the walls? If not how do you reduce sound coming in through the roof?
Thanks

beaker141

I've found the noisiest part of the velux is the metalwork surrounding it outside when it rains - I'm not in the loft so I have never looked at what can be done to reduce it.

Smiley_Dan

A lot depends on what the heat loss will be. Has this been calculated?

Basically, you need to avoid over heating you need to reduce solar gain. That means both through the windows and the roof itself. If the roof itself is insulated that helps, but also look at the decrement delay of the insulation - a higher DD helps further. Some insulants like cellulose are good for this.

Bear in mind that having more insulation in the roof can then make things worse if the solar gain through the window is high enough. So to counter that, spec a window that is either smaller, facing a different way, or have external shutters (not sure if you can get them on velux).

Basically, it's physics, so get your calculator out.

zoothornrollo_2

Thanks both.

phil24_7

Soundboard is great stuff, as is using dense insulation but I have my doubts about whether this can be used on the roof. The plasterboard is about twice as heavy as standard board and heavier again than 9mm board (which they will probably want to use to keep the weight down).

I would also recommend keeping a good amount of insulation between the loft and the floor below to try to stop as much heat rising from the rest of the property as possible.

Browntoa

I got velux blackout blinds to cut out the sun in my loftspace

zoothornrollo_2

phil24_7 wrote: »

Soundboard is great stuff, as is using dense insulation but I have my doubts about whether this can be used on the roof. The plasterboard is about twice as heavy as standard board and heavier again than 9mm board (which they will probably want to use to keep the weight down).

I would also recommend keeping a good amount of insulation between the loft and the floor below to try to stop as much heat rising from the rest of the property as possible.

Thanks Phil.

1) So I take it it would have to be a 'stud wall' to fit in Rockwool as well as soundcheck board and maintain a gap between the insulation and the brick wall? This is the bit I am not clear about. Not actually totally sure what a stud wall is and what the alternative is, and why and when a builder would use one over the other, etc.

2) I was under the impression that the amount of thermal insulation stipulated by building regs is pretty thick - would I really need to ask for more? I know that height is an issue in my loft space - there was only just enough clearance to the roof apex to convert, so the floor cannot be raised any more than is absolutely necessary.

Smiley_Dan

No, building regs is lowest allowable standard. You should be speccing more insulation whenever possible.

Furts

I am worried about this thread.

A loft conversion is subject to Buildings Regulations, and all savvy consumers should submit a Full Plans Application for this. This means fully detailed working drawings being prepared. Further, these should be scrutinised very carefully before submission. Basically, do they meet the requirements of the consumer?

Matters get more worrying in the case of OP because there are specific requirements to be met - overheating from south facing windows and eliminating aircraft noise. These must be designed in as part of the submission. It is no good saying to the Inspector in three months time the plasterboard has been changed, or it is rejected because it was never suitable.

In essence, both ventilation and thermal mass will need to be introduced. This might be as simple as an extract fan, or hit and miss ventilators, or a wet plastered gable walls, or who knows what because none of us have seen the situation.

To then see reference to introducing dormer windows make me wonder if a Planning Application has been considered, If so, this should come before applying for Buildings Regulations.

Back to OP - you say work is imminent but I am wondering if you have jumped the gun here?

zoothornrollo_2

Furts wrote: »

Back to OP - you say work is imminent but I am wondering if you have jumped the gun here?

We have planning permission. Building reg.s inspector not yet been consulted - the loft company is dealing with that. Will be at least six weeks before building starts.

Furts

zoothornrollo wrote: »

We have planning permission. Building reg.s inspector not yet been consulted - the loft company is dealing with that. Will be at least six weeks before building starts.

Have you scrutinised all the working drawings and the specification for the work? The fact that the loft company is dealing with that is worrying. This is your responsibility and any comeback is on you.

You have specific requirements, so to just say "the loft company is dealing with that" is, please forgive me for stating this, extremely foolish.