Hi, Long term reader, first time poster here. I've recently moved in to a ground floor flat in a Victorian house. The floor in one of the rooms was particularly squeaky so I decided to have a look over the weekend. This is what I found underneath, below the carpet and the 18mm plywood floor. No wall-plates, no noggins, half of the packers below joist were completely loose:
We would like to put engineered wood floor so I would be great to accommodate additional 5-10 mm compared to what it used to be with the carpet. I would like to add some thermal insulation because the room tends to get quite cold in the winter.
Previous owners told us that the last renovation was done around 20 years ago and it seems that the whole property has similar floor (through the exposed gaps I managed to have a look using an endoscope). Visible in the photo, is this hole under the radiator that ends with an air bric. There seems to be another one next to the main entrance (about 10 m away). The bottom concrete slab is very uneven, but completely dry. There are no signs of damp and joists (45 x 95 mm) are in really good shape. The PVC heating pipes and electricity cables are quite loosely attached to the concrete and the space below joists is only around 50 mm (see the inset in the second photo below).
I am considering two possibilities at the moment, but I am sure there are more ways to renovate this floor:
1. Removing the joists and laying a floating floor directly on top of the slab (DPM, 100 mm Celotex/PIR, 18 mm ply, underlay and engineered floor). Problems: 1) uneven slab - would need to screed, 2) filling all the space with insulation would leave no space for pipes and wires - would need to cut channels in the slab. Overall, this would give much better thermal insulation, but the would also affect the air circulation / ventilation.
2. Leave it as it is and only level up the joists, put PIR/Celotex between them, then 18 mm ply, underlay and engineered floor. Problems: 1) leveling the joists would be a bit of a challenge, 2) thermal insulation would be only max. 40-45mm. Overall, this would keep the ventilation in the ~5cm space below the joist, so more less as it is now.
Would either of these two options be preferred? Also, please let me know if you have any other suggestions.
We would like to put engineered wood floor so I would be great to accommodate additional 5-10 mm compared to what it used to be with the carpet. I would like to add some thermal insulation because the room tends to get quite cold in the winter.
Previous owners told us that the last renovation was done around 20 years ago and it seems that the whole property has similar floor (through the exposed gaps I managed to have a look using an endoscope). Visible in the photo, is this hole under the radiator that ends with an air bric. There seems to be another one next to the main entrance (about 10 m away). The bottom concrete slab is very uneven, but completely dry. There are no signs of damp and joists (45 x 95 mm) are in really good shape. The PVC heating pipes and electricity cables are quite loosely attached to the concrete and the space below joists is only around 50 mm (see the inset in the second photo below).
I am considering two possibilities at the moment, but I am sure there are more ways to renovate this floor:
1. Removing the joists and laying a floating floor directly on top of the slab (DPM, 100 mm Celotex/PIR, 18 mm ply, underlay and engineered floor). Problems: 1) uneven slab - would need to screed, 2) filling all the space with insulation would leave no space for pipes and wires - would need to cut channels in the slab. Overall, this would give much better thermal insulation, but the would also affect the air circulation / ventilation.
2. Leave it as it is and only level up the joists, put PIR/Celotex between them, then 18 mm ply, underlay and engineered floor. Problems: 1) leveling the joists would be a bit of a challenge, 2) thermal insulation would be only max. 40-45mm. Overall, this would keep the ventilation in the ~5cm space below the joist, so more less as it is now.
Would either of these two options be preferred? Also, please let me know if you have any other suggestions.
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