Globalti
Legendary Member
OK, please bear with me on this.
Our utility room is 2650mm x 2650mm, so 7m2. It's unheated and since we had the new condensing boiler fitted it is freezing as there's no big lump of cast iron giving off heat like there was with the old boiler. It's also outside the main mass of the house so gets very cold.
Floor is about 3" of concrete on top of bison beams and blocks over a void. When we fitted the new boiler we removed the tiles and tidied the floor up with a few mm of a water-based self-leveller. This has brought the floor to the same level as in the adjacent kitchen where instead of concrete screed, polystyrene slabs were laid down with t&g chipboard on top, a creaky and flexy but very warm floor covering.
Running right across the middle of the floor and through the kitchen door are the gas pipe and the F&R pipes for the downstairs heating circuit, hidden in a conduit.
Once kitchen units, washing machine etc. are installed the remaining open area to be heated will be around 4 m2.
Now, the first option is electric: lay insulation board then cable or cable mat then fill with a latex levelling compound, cost about £450 for materials. There's a fused spur handy for this.
The problem: this would add another 10 - 20mm to the floor bringing it well above the adjacent kitchen. Also Mrs RR would run it all the time, probably also with the window open for ventilation because she uses the utility to dry clothes, so the electric bill would be massive.
Second option is hot water. This would mean excavating all the concrete right down to the blocks, laying some kind of insulation, plastic pipes on top and connecting to the CH circuit. It would need isolators so this connection would need to be outside the floor (it would end up hidden inside the kitchen units). Then fill around the pipes with concrete or a flexible self-leveller.
The benefit: the mass of the floor becomes a big storage radiator and once warmed up, won't add much to the thermal load on the boiler. With TRVs on all the house radiators it can even warm the room when the rest of the rads are partially shut down. We have a heated warehouse at work for viscous raw materials and I am really impressed with the efficiency of the warm concrete floor.
Question: would it be worth bringing the pipework out of the floor somewhere ouside the kitchen units in order to include a TRV in the circuit?
Question: what do you think of the relative merits of both systems? I'm not so worried about the installation cost, I'm more concerned about the long term operating costs and the reliability of the system.
Our utility room is 2650mm x 2650mm, so 7m2. It's unheated and since we had the new condensing boiler fitted it is freezing as there's no big lump of cast iron giving off heat like there was with the old boiler. It's also outside the main mass of the house so gets very cold.
Floor is about 3" of concrete on top of bison beams and blocks over a void. When we fitted the new boiler we removed the tiles and tidied the floor up with a few mm of a water-based self-leveller. This has brought the floor to the same level as in the adjacent kitchen where instead of concrete screed, polystyrene slabs were laid down with t&g chipboard on top, a creaky and flexy but very warm floor covering.
Running right across the middle of the floor and through the kitchen door are the gas pipe and the F&R pipes for the downstairs heating circuit, hidden in a conduit.
Once kitchen units, washing machine etc. are installed the remaining open area to be heated will be around 4 m2.
Now, the first option is electric: lay insulation board then cable or cable mat then fill with a latex levelling compound, cost about £450 for materials. There's a fused spur handy for this.
The problem: this would add another 10 - 20mm to the floor bringing it well above the adjacent kitchen. Also Mrs RR would run it all the time, probably also with the window open for ventilation because she uses the utility to dry clothes, so the electric bill would be massive.
Second option is hot water. This would mean excavating all the concrete right down to the blocks, laying some kind of insulation, plastic pipes on top and connecting to the CH circuit. It would need isolators so this connection would need to be outside the floor (it would end up hidden inside the kitchen units). Then fill around the pipes with concrete or a flexible self-leveller.
The benefit: the mass of the floor becomes a big storage radiator and once warmed up, won't add much to the thermal load on the boiler. With TRVs on all the house radiators it can even warm the room when the rest of the rads are partially shut down. We have a heated warehouse at work for viscous raw materials and I am really impressed with the efficiency of the warm concrete floor.
Question: would it be worth bringing the pipework out of the floor somewhere ouside the kitchen units in order to include a TRV in the circuit?
Question: what do you think of the relative merits of both systems? I'm not so worried about the installation cost, I'm more concerned about the long term operating costs and the reliability of the system.
