Sometime ago, about 2 months, I posted a note on the General Comments area about under floor heating (UFH). At the time I had decided our home, which has a cellar, was in need of this as when the temperature fell below -5 degrees C our feet would freeze while our heads would boil. Even after insulating, the problem was not fully resolved. Anyway, I thought it might be a good time to post something on the outcome of my installation.
First, for those that either don't remember my posting or didn't read it, here's a little background to to the story.
We had decided we would like to install veneered flooring throughout the lower part of the house, excluding the kitchen, which had already been fitted with ceramic tiles. As we had been having so much trouble with the floor's insulation I had decided we would take up the existing floor, install 50mm of polyurathane foam insulation, UFH and install T & G panels.
Initially I had intended to router a channel into the floor to accept the UFH pipe, as it turned out this was not necessary and the pipes were fitted between the joints above the insulation.
Research and resources
Like any job that requires a major change to the central heating system, it's a good idea to do you research first. I spent about a year mining for information, invited reps from various companies to discuss it with me and even had one company rep visit the site. In principle it's quite a simple thing to install, in practice it requires you to have a comprehensive knowledge of building, electrics and plumbing, so I would not suggest this project to anyone that does not have these qualities.
The materials and costs
As I said earlier, in principle UFH is straight forward. It's little more than a pipe that weaves back and forth under the floor and is fed from your existing boiler. The hot water which would normally feed a radiator is used to heat the floor rather than your walls and ceilings. Choosing your materails will depend on how long the the UFH pipe needs to be and the capacity of your existing boiler.
Initially the costs of the system seemed to be in excess of £1700 if you included the new insulation. This was well above my budget for the job, so I consulted with some experts in the USA and a company here in England. It seemed if I laid the pipe as required and used small rads for each zone, (400x500mm) to capture any excess air and attached Limiter Valves to these and also added one additional pump to the system, I should get the desired effect.
I have 3 zones on my circuit, the total pipe needed was about 130 meters, this would give about 45 sq. meters of heated floor. The PolyPlumb pipe, came to £150.00 the additional pump £50, the rads, £46 and the limiter valves £72. As the floor was to be renewed anyway and the insulation would have been installed at that time with or without UFH the costs is really a BTW, but for those that are intersted the insulation and floor panels can to £183.00.
The Problems
Normally when installing UFH it's advisable to do a pressure check in the pipe. This entails connecting a special pump to the system and pumping in water until the correct test pressure is reached. As I have a boiler which tells me the pressure of the system I used this for my tests. The pressure chck showed no problems.
Initially it was undecided whether an additional pump would be needed. The manufacturer of the boiler said it wouldn't be needed while the manufacturers of the the UFH systems said it would be needed. So once the first Zone was installed I turned on the boiler to see if it would work, it did. However, when the second Zone was installed the circulation of the heated water was insufficient and it was clear the added pump would have to be installed. Added to this our supplier had some trouble getting the Limiter valves. Some of the problems they had were self inflicted, that is they just didn't do their job right, and some of the problem was related to the rarity, or so the supplier said, of the limiter valve's angled censor we wanted. Either way, we had to do our checks without the valves, and without these valves the system of pipe and rads could not be easily balanced, however we over came this by adjusting to flow through the system with ordinary rad valves.
Another small, but self inflicted problem was I hadn't tightened the pipes correctly to the pump, which meant the system lost pressure over night and emptied a small amount of water into the cellar. Not a big problem but it meant that the combi boiler wouldn't fire up until the pressure had been restored, and a cold start to my day, at least when I got out of bed and for the first half hour...I can hear you all having a good cry on my behalf
Summary
Wood floors are very popular and one thing that might stop some people installing them is the comfort level, i.e., if the floor looks and feels cold then carpets are a clear choice. UFH overcomes the problem of the floor feeling cold. However, it has been generally true that UFH is expensive to install and the 'pay back', that is, the time it takes to get back your investment on the savings made from the installation could be quite long, in fact so long you could be dead before it paid for itself. However, the system I've installed cost £410.00, possibly £450 if you allow for misc. parts such as pipe clips etc...For this investment, I have a heating system that warms the room in a comfortable way, from the feet instead of from the head. The fuel cost should fall, as once the floor is heated it remains stored in the floor itself and released over a period of time, only topping up with heat in short intervals. Of course the key feature is in the insulation, this must be right or any savings will be lost.
For anyone thinking of installing UFH, I can highly recommend it, the warmth is entirely different, you feel warm yet the room has none of the stuffy qualities normal rads give.
Some might say that the floor makes for an expensive rad, which is true. However levelled against this, the floor holds it heat for longer and therefore requires much less work from the boiler making it much cheaper to operate. However I'll post something next year once I have some idea of the true savings.
As for the installation, it's about as disruptive as it gets. The whole floor has to come up, so if you've just decorated you may want to hold off for a while, you will also need a partner or wife/husband with the patients of a saint, that trusts you completely, and a hot line to God also helps as your prays need to be answered a lot
First, for those that either don't remember my posting or didn't read it, here's a little background to to the story.
We had decided we would like to install veneered flooring throughout the lower part of the house, excluding the kitchen, which had already been fitted with ceramic tiles. As we had been having so much trouble with the floor's insulation I had decided we would take up the existing floor, install 50mm of polyurathane foam insulation, UFH and install T & G panels.
Initially I had intended to router a channel into the floor to accept the UFH pipe, as it turned out this was not necessary and the pipes were fitted between the joints above the insulation.
Research and resources
Like any job that requires a major change to the central heating system, it's a good idea to do you research first. I spent about a year mining for information, invited reps from various companies to discuss it with me and even had one company rep visit the site. In principle it's quite a simple thing to install, in practice it requires you to have a comprehensive knowledge of building, electrics and plumbing, so I would not suggest this project to anyone that does not have these qualities.
The materials and costs
As I said earlier, in principle UFH is straight forward. It's little more than a pipe that weaves back and forth under the floor and is fed from your existing boiler. The hot water which would normally feed a radiator is used to heat the floor rather than your walls and ceilings. Choosing your materails will depend on how long the the UFH pipe needs to be and the capacity of your existing boiler.
Initially the costs of the system seemed to be in excess of £1700 if you included the new insulation. This was well above my budget for the job, so I consulted with some experts in the USA and a company here in England. It seemed if I laid the pipe as required and used small rads for each zone, (400x500mm) to capture any excess air and attached Limiter Valves to these and also added one additional pump to the system, I should get the desired effect.
I have 3 zones on my circuit, the total pipe needed was about 130 meters, this would give about 45 sq. meters of heated floor. The PolyPlumb pipe, came to £150.00 the additional pump £50, the rads, £46 and the limiter valves £72. As the floor was to be renewed anyway and the insulation would have been installed at that time with or without UFH the costs is really a BTW, but for those that are intersted the insulation and floor panels can to £183.00.
The Problems
Normally when installing UFH it's advisable to do a pressure check in the pipe. This entails connecting a special pump to the system and pumping in water until the correct test pressure is reached. As I have a boiler which tells me the pressure of the system I used this for my tests. The pressure chck showed no problems.
Initially it was undecided whether an additional pump would be needed. The manufacturer of the boiler said it wouldn't be needed while the manufacturers of the the UFH systems said it would be needed. So once the first Zone was installed I turned on the boiler to see if it would work, it did. However, when the second Zone was installed the circulation of the heated water was insufficient and it was clear the added pump would have to be installed. Added to this our supplier had some trouble getting the Limiter valves. Some of the problems they had were self inflicted, that is they just didn't do their job right, and some of the problem was related to the rarity, or so the supplier said, of the limiter valve's angled censor we wanted. Either way, we had to do our checks without the valves, and without these valves the system of pipe and rads could not be easily balanced, however we over came this by adjusting to flow through the system with ordinary rad valves.
Another small, but self inflicted problem was I hadn't tightened the pipes correctly to the pump, which meant the system lost pressure over night and emptied a small amount of water into the cellar. Not a big problem but it meant that the combi boiler wouldn't fire up until the pressure had been restored, and a cold start to my day, at least when I got out of bed and for the first half hour...I can hear you all having a good cry on my behalf
Summary
Wood floors are very popular and one thing that might stop some people installing them is the comfort level, i.e., if the floor looks and feels cold then carpets are a clear choice. UFH overcomes the problem of the floor feeling cold. However, it has been generally true that UFH is expensive to install and the 'pay back', that is, the time it takes to get back your investment on the savings made from the installation could be quite long, in fact so long you could be dead before it paid for itself. However, the system I've installed cost £410.00, possibly £450 if you allow for misc. parts such as pipe clips etc...For this investment, I have a heating system that warms the room in a comfortable way, from the feet instead of from the head. The fuel cost should fall, as once the floor is heated it remains stored in the floor itself and released over a period of time, only topping up with heat in short intervals. Of course the key feature is in the insulation, this must be right or any savings will be lost.
For anyone thinking of installing UFH, I can highly recommend it, the warmth is entirely different, you feel warm yet the room has none of the stuffy qualities normal rads give.
Some might say that the floor makes for an expensive rad, which is true. However levelled against this, the floor holds it heat for longer and therefore requires much less work from the boiler making it much cheaper to operate. However I'll post something next year once I have some idea of the true savings.
As for the installation, it's about as disruptive as it gets. The whole floor has to come up, so if you've just decorated you may want to hold off for a while, you will also need a partner or wife/husband with the patients of a saint, that trusts you completely, and a hot line to God also helps as your prays need to be answered a lot
