Hello - I need advice regarding internal wall insulation

#1
I live in a 1930s house near Croydon, the external walls are not insulated neither does it have any gaps between the bricks. I am planning to insulate the inside wall surrounding the window in the upstairs bedroom (size 13"x11").The walls are very crumbly and the plaster has come off in places. We decorated this room years ago in the early 1980s.
My plasterer suggested using a thicker insulated plasterboard round the wall and round the window slightly thinner insulated plasterboard to fit the width round the frame. I have read online that the internal walls can also be insulated using wooden strip batons and then insulated in between. I have fitted wardrobes on one side along the chimney breast. He would also have to insulate the external wall inside the fitted cupboard.
I am not sure what is the difference between the ready made insulated plasterboard or inserting insulation between the batons. My plasterer said that putting batons up will be more expensive alternative.
Also, are insulated plaster boards fireproof?
I also have very heavy curtains. Will it be easy to drill holes and would the plasterboard be able to support the weight of the heavy curtains?
There is a radiator under the window which would have to be moved slightly forward to accommodate the insulated wall. There are pipes in the corner which I don't believe are functional any more.
How much would it cost approx? I have asked the plasterer to plaster 3 walls, two internal walls and one external and the ceiling which has a crack going right across the room. We can't plaster the other fourth wall as it is surrounded by fitted wardrobe.

I would also like to get extra sockets put in the room. Can anyone recommend a qualified electrician and a plumber to take off the radiator and move it forward after the plasterboarding?

Thank you.
 

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#2
Empty water, remove radiator, remodel pipes for radiator. Pull wire for socket. Fix electical socket box (not necessary). Create metal or wood frame for platerboard. Fit mineral wool insulation boards - 8cm thick. Add vapor membrane and close with plasterboards, can use fireboard. You will need a new window board. Install radiator to new position. Complete electrrical socket. Go through jointing and plastering steps. Paint new wall.
 

John j

Well-Known Member
#4
Why do they need to be fire boards. Knock plaster of . Move rad pipes . Get first fix for new socket. . Dot qood thickness and good quality insulation boards on . Long screws for curtain pole or put a plinth up or get a blind lol
 
#5
Insulated plaster 80mm for north facing wall, 50-60mm for east, west, south facing walls, may be a good solution as well, but it would contain some foam material, if you are allright with it.
 
#6
Your level of insulation will be determined on how much room you can afford to lose on your walls.

a good system I found if space is an issue is:

Treated stud timber on walls fixed at 300mm intervals,25mm celotex/kingspan etc.. in between batons then 27 mm gyproc thermaline plus insulated plaster boards.

I would never dot & dab any type of plasterboard onto an external wall with no cavity.

Internal walls can be just dot & dabbed with standard plasterboard.

Your fixings for radiator/curtain poles etc....can be dealt with at baton fixing stage, just place extra timber on wall where they are going to hang.
 

John j

Well-Known Member
#7
Your level of insulation will be determined on how much room you can afford to lose on your walls.

a good system I found if space is an issue is:

Treated stud timber on walls fixed at 300mm intervals,25mm celotex/kingspan etc.. in between batons then 27 mm gyproc thermaline plus insulated plaster boards.

I would never dot & dab any type of plasterboard onto an external wall with no cavity.

Internal walls can be just dot & dabbed with standard plasterboard.

Your fixings for radiator/curtain poles etc....can be dealt with at baton fixing stage, just place extra timber on wall where they are going to hang.
Done all my upstairs no probs
 
#8
Polyurethane foam adhasive can be used as alternative. Either way it would be advantageous to clean the old wall and pva it before going further. Not that anyone does it ).
 
#10
For sure it would be better fixed if frame would be mechanically fixed to brick wall, and plasterboard fixed to a frame. Would be resistant to outside elements. But with thick brick wall, very low chance of that happening in my opinion.
Even if dot n dab loosens at few places over time, easy fix is to drill a small hole where it is loose and fill in with polyurethane foam adhesive with PU gun.
 
#11
Thank you for all your replies.
I want to insulate the wall from inside, not insulate the external walls of the house.
What is the best thickness Recommended for ready insulated plasterboard? I would like the room to be really warm in the winter.
 
#12
Why do they need to be fire boards. Knock plaster of . Move rad pipes . Get first fix for new socket. . Dot qood thickness and good quality insulation boards on . Long screws for curtain pole or put a plinth up or get a blind lol
What would you recommend for good thickness and good quality insulation boards?
 
#19
Thank you for all your replies.
I want to insulate the wall from inside, not insulate the external walls of the house.
What is the best thickness Recommended for ready insulated plasterboard? I would like the room to be really warm in the winter.

when we describe external walls,we mean window/external doors/non party walls pal not actually the outside of them
 
#20
Could I ask what’s the budget?
I don't mind spending more money, if the plaster will last me for a long time and also if the insulation provided by the insulated plasterboard is very effective and keeps the room warm.
I don't work by budgets because I have never done this before and wouldn't have a clue as to how much this job would cost.
 
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Vincey

Private Member
#21
I don't might spending more money, if the plaster will last me for a long time and also if the insulation provided by the insulated plasterboard is very effective and keeps the room warm.
I don't work by budgets because I have never done this before and wouldn't have a clue as to how much this job would cost.
Thanks, I just completed a full upstairs and hall stair landing areas for a client , all in was £6500 which tbf is a good lump sum to pay out but the client had worked out his energy saving costs to get the pay back within 9 years on his total improvements, he also had boiler and windows done at extra by someone else

I’d advise check out energy saving trust website to see ball part figures of installation and cost savings once the works done ,
 
#23
Your level of insulation will be determined on how much room you can afford to lose on your walls.

a good system I found if space is an issue is:

Treated stud timber on walls fixed at 300mm intervals,25mm celotex/kingspan etc.. in between batons then 27 mm gyproc thermaline plus insulated plaster boards.

I would never dot & dab any type of plasterboard onto an external wall with no cavity.

Internal walls can be just dot & dabbed with standard plasterboard.

Your fixings for radiator/curtain poles etc....can be dealt with at baton fixing stage, just place extra timber on wall where they are going to hang.
Why would you never dot and dab plasterboard onto an external wall with no cavity? I am assuming you are talking about an inside wall which is the main outside wall of the house.