Replacing an old ceiling - Insulation.

[eastender3]

Iam replacing a bedroom ceiling and lowerground lounge ceiling. The house is a 30s terraced house. The ceiling lath and plaster will be replaced by plasterboard and then skim over it.

Now the insulation, is it normal practice to get plasterboards that have built in insulation or do you add insulation in other ways. Sorry never replaced a ceiling before.

 

[roy c]

If you can get to the ceiling from above(From loft area) and it is easy to lay your insulation inbetween the joists when it is boarded then that is one option. The other one is to put the insulation between the joists before plaster boarding. You can buy rolls of insulation that come in 1200mm rolls some uncut(that you can cut your self with a wood saw to the size you want) and others that have been machine cut into 2x 400mm that have been part cut that you can put your hands in the cut or "rip" it from the roll (make sure you wear gloves) when I do this I usually use rubber gauntlets that come right up my forearm .And 1x 200x200mm roll that is good for filling in narrow areas, If you are setting out your new ceiling them you can set them at 400m centres ( middle of joist to middle of joist) then your insulation will fit nicely between the joists. If you are putting it between existing joists then you should be ok squeezing the insulation between as the old joists can vary from 12" 14" to 16" centres. Now the important part....Wear a paper disposable suit, a good quality face mask, a hat Goggles if you can (rub some washing up liquid on the lenses to stop any misting up. And like I do a pair of rubber gauntlets.
,and a good sharp stanley knife. When you come to cut the lengths of insulation it will swell up as soon as you unroll it so get your self a piece of batten(2"x1") 4inches bigger than the width of insulation and lay it across the insulation and measure it from the edge to front of batten then press the batten down with your hand and cut through it with the stanley (keep your hand away from front edge!!!!! And there you have it,, Good luck

 

[eastender3]

Thanks for the reply Roy.

I'll do that for the Bedroom ceiling and lay insulation blanket via the loft and lay between the joists.

Now for the lounge and hall way ceiling, can I put insulation between joists before plasterboarding, for soundproofing, which would be the main purpose. Do you use the same type of insulation that you put in the loft, for the lower ground ceiling, or something differant.

Not sure if normally people use insulation for lower ground ceiling.

Thanks.

 

[roy c]

I have insulated down stair rooms but you will have to check out what systems there are for sound proofing ,its not as easy as putting in normal insulation and hope it deadens the sound . We sound proofed a building 10 years ago and it involved a lot of materials that wouldn't be practical in a house (taking up floor boards and putting insulated panels suspended on metal strips with foam rubber supporting them )and same idea on the ceilings with 20mm plaster board laths in between the joists then double boarded. This building was to be offices...Good carpets and underlay will kill a little bit of sound and 20mm plaster board or double boarded with sound boards on the ceilings and insulation inbetween joists might help, but some of the other lads might have better knowledge of this than me.

 

[eastender3]

I have insulated down stair rooms but you will have to check out what systems there are for sound proofing ,its not as easy as putting in normal insulation and hope it deadens the sound . We sound proofed a building 10 years ago and it involved a lot of materials that wouldn't be practical in a house (taking up floor boards and putting insulated panels suspended on metal strips with foam rubber supporting them )and same idea on the ceilings with 20mm plaster board laths in between the joists then double boarded. This building was to be offices...Good carpets and underlay will kill a little bit of sound and 20mm plaster board or double boarded with sound boards on the ceilings and insulation inbetween joists might help, but some of the other lads might have better knowledge of this than me.

Cheers Roy for your reply and kind advice.

I think I'll just put normal insulation between the joist and will put carpets and underlay upstairs, which will be be the case anyway.

So people do use insulation on ground floor ceiling, I had thought people don't bother and only put insulation on loft. Someone told me that heat only escapes through the ceiling to the bedrooms, so no need to put insulation on downstairs.

 

[roy c]

I wouldn't think that there would be enough heat escaping to give any noticeable difference in the bedrooms. But it would keep heat in your down stair rooms and make them warmer.

 

[eastender3]

Roy, I've reading a bit more about plastering depth and most recomend 9 or 12.5mm thickness of the board, the latter is mostly prefered. So 20mm could be very thick indeed.