Hello,
I am considering buying a property that has a small house in dire need of weatherproofing renovation that includes:
- Roof replacement
- Drainage
- Replacement of facade/panel
Since the house was built in 1945, it is not particularly well-insulated, so I plan to take the opportunity to insulate while performing the above renovations.
The house has a basement, which is made of hollow concrete blocks and rests on footings with a floating concrete floor. The main floor is a timber construction, I suspect a plank frame with sawdust as insulation.
Insulating the basement wall below ground is not a difficult task; I was thinking of using 100mm isodrän/pordrän or equivalent.
For the main floor, I am in line with adding insulation behind the panel with air gaps according to standard practices.
My dilemma is:
The basement is not completely dug in; there is about 80cm above ground with some windows. Of course, I want to try to insulate these parts as well and want to plaster the visible foundation/basement wall.
Should I:
Option #1: Extend the isodrän to 10cm below ground level as usual, fold in the geotextile, add the drip edge/cover strip, and then stack up cell plastic above ground all the way to the panel and the horizontal batten, abutting it, and then plaster on the cell plastic?
Option #2: Extend the isodrän all the way up to the panel like option #1, but finish the geotextile at a board joint below ground level and plaster directly on the isodrän board?
Option #3: Same as Option #1 but without the cover strip between the isodrän and cell plastic.
In general, I plan for the panel to hang over the plastered wall, and the drip edge of the panel should be 5-10cm below the top edge of the plastered basement wall.
Or do you have any other good suggestions? I am reluctant to insulate from the inside, as I plan to have plastered walls from the inside.
What type of plaster should be used for this?
I am considering buying a property that has a small house in dire need of weatherproofing renovation that includes:
- Roof replacement
- Drainage
- Replacement of facade/panel
Since the house was built in 1945, it is not particularly well-insulated, so I plan to take the opportunity to insulate while performing the above renovations.
The house has a basement, which is made of hollow concrete blocks and rests on footings with a floating concrete floor. The main floor is a timber construction, I suspect a plank frame with sawdust as insulation.
Insulating the basement wall below ground is not a difficult task; I was thinking of using 100mm isodrän/pordrän or equivalent.
For the main floor, I am in line with adding insulation behind the panel with air gaps according to standard practices.
My dilemma is:
The basement is not completely dug in; there is about 80cm above ground with some windows. Of course, I want to try to insulate these parts as well and want to plaster the visible foundation/basement wall.
Should I:
Option #1: Extend the isodrän to 10cm below ground level as usual, fold in the geotextile, add the drip edge/cover strip, and then stack up cell plastic above ground all the way to the panel and the horizontal batten, abutting it, and then plaster on the cell plastic?
Option #2: Extend the isodrän all the way up to the panel like option #1, but finish the geotextile at a board joint below ground level and plaster directly on the isodrän board?
Option #3: Same as Option #1 but without the cover strip between the isodrän and cell plastic.
In general, I plan for the panel to hang over the plastered wall, and the drip edge of the panel should be 5-10cm below the top edge of the plastered basement wall.
Or do you have any other good suggestions? I am reluctant to insulate from the inside, as I plan to have plastered walls from the inside.
What type of plaster should be used for this?
I chose option 1. The foam plastic was attached both with a special plug and glued. I tested both fiberglass reinforced render and regular render mix c. I also used render mesh, of course. All of this has only been in place for a year (barely), so I can't evaluate the different methods long-term yet. Both look good so far.
Is it the mesh that ensures it doesn't crack at the seam between the insulation boards?
....and what should the transition between insulation and isodrän look like? I believe it's common to finish with some kind of metal sheet?
....and what should the transition between insulation and isodrän look like? I believe it's common to finish with some kind of metal sheet?
If we start with option 1, doesn't it create a thermal bridge between cellplast and isodrän? The edging strip has a slope and doesn't allow full contact on either cellplast or isodrän unless you bevel the edges.
In my view, these two different board materials should be placed tightly against each other and wedge the geotextile fabric between them if you want to avoid a thermal bridge.
How good is it really to have cellplast directly against the foundation and plaster on the cellplast? Should there be an air gap behind it? I'm not so familiar with cellplast, but something tells me that cellplast doesn't breathe very well, or are there different types of cellplast for different purposes?
You want the plastered cellplast to go down a bit into the ground; should you apply some kind of waterproofing on the plaster? Paint it with some sealant? The part that goes into the ground and 5-10 cm up on the plinth... Or is that overdoing it?
In my view, these two different board materials should be placed tightly against each other and wedge the geotextile fabric between them if you want to avoid a thermal bridge.
How good is it really to have cellplast directly against the foundation and plaster on the cellplast? Should there be an air gap behind it? I'm not so familiar with cellplast, but something tells me that cellplast doesn't breathe very well, or are there different types of cellplast for different purposes?
You want the plastered cellplast to go down a bit into the ground; should you apply some kind of waterproofing on the plaster? Paint it with some sealant? The part that goes into the ground and 5-10 cm up on the plinth... Or is that overdoing it?
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No more opinions or ideas? =)