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Found 72 results

  1. In the parents new wet room (the foundations are being done tomorrow), we shall have a concrete floor over insulation. As its for elderly folks who feel the cold, I need to make sure the room is warm enough for them. We only have electric in the bungalow and no central heating (its a warm air system). So my plan is electric mat UFH, tiling over it, and an electric heated towel rail on a timer to come on in the morning about an hour before they have a shower. I am looking at the following for the UFH. the room is 2.7m by 1.8m with units along one wall so am looking at a system to cover about 3.5m2. But Dad is worried about the cost of running it. What can I tell him? Presumably it only heats when it needs to come up to temperature so it will not be on all the time. Any advice welcome!
  2. I have posted previously about some design questions here I have settled on a thermal store with 2 ufh manifolds and a radiator circuit. Looking some direction on my thoughts of how to connect this all to thermal store. - Boiler connected via 2 port valve controlled by tank stats. 2 tank stats controlled via time clock one for summer (no ufh demand) one for winter. - UFH zones and rads off a single tapping from thermal store, or should I separate rads to their own tapping? Either way each will have a 2 port valve. - UFH pumps connected via the switched live from the zone valves, think I seen @Nickfromwales recommend this previously. - Rads will be controlled from time clock and 2 port valve triggering their own pump. Is this correct? Should I do it different, I don't mean ashp instead of boiler? Have I missed anything? As always thanks in advance.
  3. I am annoyed this morning. Once again my washing-up water - the first hot water I have used in the kitchen today - is running warm then cold then hot. And the cold water is running warm then cold. This probably means that the last people, who renovated the house, did not insulate the water pipes where they pass through the zone where there is underfloor heating, and the water standing in the pipes has heated up. A small annoyance due to lack of sweat applied to the detail. But one that is noticeable and about which I can do nothing practically. Boo !
  4. Hi all, I am just completing a conversion but hired professionals for UFL. What I find strange is that the manifold (RED) is in the kitchen, and all sections (4 excluding kitchen) go through the kitchen floor and not through the staircase (behind the kitchen) and therefore leaving the potential to overheat the kitchen, when all areas are on and kitchen is already at temperature. Should't they have taken into consideration that the kitchen is potentially the warmest place in the house and it will become a potential sauna? Also the Manifold is right behind the oven and stove. Can I should I insulate the pipes from the screed? Will lay down normal sand+cement screed... Any pointers really appreciated. Thanks
  5. I was just lloking into the different systems available for heating/Hot water. Some Great systems are used by the members on here and I am tempted to use a Genvex Combi like @PeterStarck as it seems amazing logical to combine it all with the MVHR. However, i just found this : It seems an incredible good system, even though not including the MVHR , but still a very good, space saving method which seems easy to use/install. Website is in Norge so anybody wanting a look might need to look at their NZ distributor as I couldn t find UK or even US website Anybody on here ever looked into this? Is it a good system, or not really worth the trouble ordering from Norway as similar exists in the uk(which ones>? )
  6. Hi, I'm new to this forum and would be grateful if someone has any advice regarding the following. We are currently building a small kitchen/diner extension and I have underfloor heating planned for it. We are tight for space so am thinking of putting the manifold in the pantry cupboard I'm planning on putting in the corner. My question is: Do manifolds give out much heat? I ask because our condenser boiler feels cool to touch when it's on. Can the manifold be adequately boxed in with insulation (but also accessible) that it doesn’t give off heat if its put in the pantry? Thanks
  7. Hi there, I've a 125m2 extension being erected next year with a pretty basic floor slab planned. Floor covering 65mm Screed UFH Pipwork 150mm PIR insulation 100mm c35 concrete with mesh Whilst looking at the overall prices of each piece of work there's a couple of questions that have come up would it beneficial to change the floor structure to incorporate circa 250mm of eps insulation under the concrete slab, instead of the 150mm pir above slab. And whilst I am at it, possible to incorporate the Under floor heating pipework into the slab, as opposed to having the pipework in a screed on top of the slab? The reason for looking at this is to save time and money. The 250mm of eps insulation has similar u value to 150mm pir, whilst being cheaper - circa 1k at the moment, but there is another price increase on pir due in February. If I incorporated the pipework into the slab, I could save circa 4k for the screed work post panel installation, but it would also mean I could crack on with the studwork immediately after the kit erection as opposed to laying pipework and ordering in self levelling screed. any thoughts/drawbacks?
  8. I am in the throes of doing my insulation in the floor. Perimeter strips will be done around external walls. Is there any great benefit in doing this on the internal walls as well rather than just the foam strip? Thanks in advance.
  9. Hi, I will email the heating engineer in the morning, but if anyone knows a simple fix I can try it today. We have 4 UFH manifolds, all has been fine until Friday. The kitchen seemed cold. I thought the thermostat maybe wasn't calling for heat correctly and checked that out. It still seemed to be slow warming up, so I went to the manifold and turned the flow up slightly. What seems to be happening is that if you turn the flow up past a certain point the water stops flowing. Basically any higher than 2 on the mixer which is 22-23C and the flow stops. Even then I had to jack the pump up to maximum to get much flow. The other manifolds are set between 36 and 42 and running as expected. Probably wasn't an issue until the temperature dropped below zero. Any thought?
  10. Evening all, Our slab was poured about 2 years ago now & with tiling down stairs now looking imminent I have been advised to heat shock the slab pre tiling (UFH). Starting off by increasing the temp by 1 - 2 degrees a day up to a max and then hold that temp for a week and then drop in back down by 1 - 2 degrees a day. The only snag is that no one seems to be able to tell me what the max temp should be, today I put it up to 23degrees - I can't see us every running it warmer than that. Does anyone know how high we need to take it to? Thanks
  11. General advice is not to turn UFH on for 2-4 weeks after laying tiles. I have used Kerakoll BioGel NO LIMITS Eco Friendly Flexible S1 Adhesive (White). The data sheet for this includes details for using it at 35°C and our UFH flow temperature is set at 37°C (in 50mm of screed). I'm getting pressure to get the heating back on.... given these temperatures do you think this is risky?
  12. I'm probably overthinking this but I've thought about it so I'll ask . I tend to have the UFH come on once a day in the evening during the week. Currently I set all rooms that I want to heat to come on at the same time a couple of hours before I arrive home from work regardless of size. The smallest room (utility) gets up to temperature pretty quickly but the largest room (kitchen / family) take 2+ hours so I wondered whether it would be more efficient to set the larger rooms to come on first and the smaller rooms a bit later. Or is that a crap idea and it would make no difference?
  13. Help needed please. We are about to order electric UFH mats for bathrooms. We need some insulation boards to go under the electric mat. Do we put the insulation boards and/ or the tiles under the bath? (a back to wall bath, no panel - it’s all one unit so sort of free standing). The basin and toilet are wall hung so the boards will go under those. Sorry, prob a daft question 😊
  14. I've been wrestling with Loopcad for sometime now and am loosing the will to live. I take 1 step forward only to follow it with 2 steps back!! Are there any kind souls out there who are proficient in using Loopcad who could help with my loop design for the ground floor and save me from tearing the rest of my hair out? I'm trying to use spiral counter-flow where possible. Here are 2 versions of the GF plan, one with dimensions and one without.
  15. Following on from a number of threads discussing electric UFH Can anyone recommend a particular make for 1.5m2 of under-tile electric UFH. The easy-to-get ones would be the Klima kits from Screwfix but I know nothing about them. Any other suggestions ?
  16. I'm fitting Wunda UFH downstairs on top of an insulated screed with laminate boards on top throughout (did want engineered wood but don't have the cash!!). My question is what thickness of laminate will be ok? We have seen some in the colour and finish we like (we've looked at hundreds as we're really fussy!) but it is only 8mm rather than the 12mm we have previously assumed would be the minimum. We have some heavy furniture and an american fridge/freezer etc and I'm worried that 8mm laminate might be too flexible and the wunda boards will end up getting compessed under the heavy items. Any thoughts?
  17. When I laid the wet UFH pipes in our concrete slab I put a loop in both bathrooms. Now I am hoping to put an electric mat under the tiles above the wet pipe system unless the collective say otherwise. Like some I am hoping to have a subtle background heat (electric)from the bathrooms to heat the house before we go full wet pipe but not sure if this is ok above the wet pipe system. TIA
  18. I know the lower U-value I achieve for my ground floor the better but is there a maximum U-value beyond which under floor heating is not advisable?
  19. Hi all, I have been offline for a month or so ...struggling to get the exterior of the house complete ... almost there ...will the weather catch up with me for 2018 ....sadly i think it might (sigh) But anyway we have been cracking along with the internal ....boarding upstairs is done and the electrics and plumbing are done on first fix ... I DPM-ed, vapoured and insulated the Beam and block and then finished with a slip sheets and last week the Plumbers installed the nu-heat UFH system and tested it ...all good so far! the screeders are coming wednesday and they are laying a grit sand and cement screed I have 16 tonnes of sharp and 80 bags of the grey stuff standing by !! But it has got me thinking about tiles ! ..well i KNOW the wife is looking at basically the ENTIRE downstairs tiled in large 300x400mm tiles that are 9mm thick ... Now ...I have had various advice ....stuff like use special grout use special adhesive use a separation or decoupling membrane dont tile for 2 months as it needs to dry as rooms are different zones it will CRACK at door openings and you need "gaps" Is there any truth to any of this ....and what can you advise PS Floor is Beam and Block with 1200 micron DPM, 500DPM Barrier/Slip, 90mm Kinspan TF Insulation with 60mm external and 25mm internal upstands and screed is set to be at 70/75mm PPSThose are temporary stairs (in case you are puzzled)..that is actually a solid wall the REAL stairs will run in from the hall
  20. Rather than a liquid screen final layer before the LVT tiles the fitters want to put down Xtrafloor® Flex Pro ( see ) which is like a floating mat with a sticky topside that the LVT goes straight onto. So much quicker installation time. Anyone know of this product as it is new to me so trying to understand its pros/cons Thanks Paul
  21. At the suggestion of Alphonsox, I've been reading the descriptions of UFH systems heated by a willis heater. I'm seriously considering using one in our barn conversion in place of the intended wood burner. However, willis heaters appear to be only for vented systems and I'd rather have unvented for ease of install. How have people dealt with this?
  22. Of getting someone to commision a boiler/ufh system when it is already installed but not commissioned or pressure tested. So much for having plumbers I can rely on. They installed the boiler and ufh control last week. Everything was supposed to be finished by last Friday but unfortunately it wasn't. They left at 8pm last Friday with promises to come back today (Thursday) to complete. Couldn't get before then because of other promised work. Message at lunchtime today to say that they couldn't make it but 'should' be able to come next Thursday or Friday. The week after next, one is going away for the week (and the van is his). Absolutely fed up with this now. I should have been able to move in next week.
  23. My upper floor, that is. Due to the vast number of MBC guys on site early last week, my upstairs was ready for the underfloor heating pipes and spreader plates to go in much earlier than my plumber had anticipated. So, fortified by all the sausage rolls and pies that his local Greggs could offer at short notice, he hot-footed it from Wales over to Deepest, Darkest Dorset late last week to put the filling in the UFH sandwich of the upper floor. MBC were due back on site this morning to get the egger boards down on the first floor, so it was a case of then or never. The downstairs UFH pipes are embedded into the concrete slab and so a different method is needed for the upstairs, and this is it. What you are looking at are aluminium spreader plates with the UFH pipe bedded into them. The spreader plates are thin sheets of aluminium with two semi-circular recesses running the length of the plates. These are stapled to the joists along their length and their job is to hold the pipe in place and also to diffuse the heat over their area. The plates are very thin, barely a couple of mm thick, I would say, and very sharp, as I found out when poking the corner of them all stacked up in the shrink wrap packaging when they first arrived. Here's what they look like individually: There were a couple of delays in getting started on Friday and as a consequence work went on till well into the evening. Nick didn't quite go to the same lengths as MBC by getting his head torch out and fitting them in the dead of night, but it was still a reasonably late evening. UFH by sunset: After some hard graft on Saturday, it was all in place and the manifold had been attached, pressurised and tested and all looks good. Once all the egger boards are on, Nick will need to come back and staple the centres of the spreader plates along their lengths to the boards above to ensure good contact and heat transfer. I did not sit idly by whilst all this effort was going on, oh no, not me. I had some very important decisions to make and these took a high level of innovation and imagination. Like, where's the best spot for the furniture in the to-be living room and where do I prefer the view? Really important. And, it turns out, that off-cuts of EPS upstand make for a really good improvised sofa. To be seen in all the best furniture showrooms soon: Having tried this, I came to a very meaningful conclusion. I need more furniture. Another thing for another day. Back to business, MBC were back on site today, a team of 4 to put the egger boards in place. You can see from the spreader plate pictures above that there is virtually no joist exposed, hence the need for screwing them down, particularly as the spreader plates will need to be attached from them underneath. The guys also used the egger adhesive along the tongue and groove runs of the board sides. Being a complete ingenue when it comes to all matters of construction, I was pondering last week what the purpose was of the hefty blocks of wood set into the recesses of the I shaped steels. Today, I found out. The posi-joists don't just rest in place, they are very firmly attached using steel thingies called roof hangers. These are they: And this is where they go: On other matters, I'm busily chasing down roofers at the moment, and they are proving difficult to get hold of. One has already declined to quote because they are so busy, but I'm working through a list of possibles, so it will get done. I've also booked in for my service alteration on the electricity - it's on a pole via an overhead line right now but will be buried eventually and the pole removed. Current date for this is 17th October, but electricity companies dance to the beat of their own drum so this could easily change. It's the big stuff back tomorrow with the final frame delivery and the upper floor being constructed. Sit tight for the next thrilling episode!
  24. In this entry I'm going to discuss in more detail how I came to choose our heating and hot water system, and how it has performed to date. As other forum members have found, deciding which fuel source and type of technology to use in a low energy house, is a challenge given the different requirements each of us has. We had three stipulations – low running costs, hot water available on tap 24/7 and maintenance of the whole house at an even and constant temperature 24/7. Having calculated our heating demand, taking the impact of solar gain, incidental household gain, human occupancy and wind speed into account, I was confident that I had a good indication of the amount of heating I would need. I was also confident, based on historical use, of the amount of hot water we as a family use. Living in an area without mains gas, my options were somewhat limited to using either oil or electricity as my fuel source. LPG was initially considered but discounted due to the lack of availability in my location. As part of the decision making process, I spent a fair amount of time carrying out a cost comparison of both oil and electricity based heating and hot water systems, using 500kWh increments from 2500kWh to 5000kWh. I considered direct electric of various type, oil and air source heat pumps, both air to water and air to air. Solar PV was also considered and costed in terms of each method of heat and hot water delivery. In line with previous cost comparisons that I had carried out, I found direct electric to be the most cost effective in terms of capital outlay and running costs when both heating and hot water demand were less than 2500 kilowatt hours each year. As heating requirement and hot water requirement increases so the balance began to tip in favour of other technologies. Oil was quickly dropped from the list as it became apparent that any rise in fuel prices over then then low point, would significantly increase running costs. Having conducted significant investigation in respect of the viability of Sunamp units, although attractive in many ways, I found that the capital outlay and running cost was simply too high to be able to justify, given that the main benefit (low heat losses) were not as critical for me as they have been for others. Part of that decision was also driven by the cost of fitting Solar PV, which in our remote location was extortionate. I looked into a non MCS DIY install, but couldn’t make the figures stack up, the break-even point being around 17 years. Much as I wanted to install PV, it didn't make any sense financially. In time, I hope to revisit PV, if and when battery storage reduces the break-even point to a more realistic timescale. A wind turbine, given our location and the virtually constant presence of wind, would have been an ideal energy source and paired with Sunamp technology, probably unbeatable. The proximity of nearby houses ruled out that option in terms of planning permission. Air to Air heat pumps were ruled out based on my own experience of them and a road test at a friends house. Neither myself or my good lady found them particularly pleasant as a heat source. Having gone through the list of options, an air to water air source heat pump, paired with a large UVC and UFH for the distribution of heat, represented the best balance in terms of capital outlay, running costs and crucially, comfort and convenience. We opted for a package from Mitsubishi Ecodan, an 8.5kW heat pump and 300 litre pre-plumbed cylinder fitted with the Mitsubishi FTC5 control panel. Given our location, we opted for the coastal model, which is treated with acrylic resin for enhanced corrosion resistance. Whilst a pre-plumbed cylinder is more expensive than a bare cylinder and associated parts, after taking labour (plumber and electrician) into account, I found there was very little difference in cost. I sourced the package from a trade supplier, Secon Solar. I found their price list while searching online and having phoned the company, and perhaps fortuitously speaking to the managing director of the firm, found they were quite happy to sell me package at trade / installer price, the bonus being that delivery to my location was free. The package is configured for the UK market, the only difference to the system as sold in the rest of Europe (AFAIK) being that the cooling function of the heat pump is disabled so that the product complies with MCS approval for claiming RHI. It is however a simple task to activate the cooling function, by flipping a dip switch in the control module on the cylinder. Cooling can then be controlled from the master controller. As stated in an earlier blog entry, the heat pump and cylinder were fitted very quickly with simple connections on the plumbing side – flow and return from the ASHP, cold water, hot water and flow and return to the underfloor heating manifold. Electrical connections consisted of power to the ASHP, a cable from the ASHP to the control module and a plug-in controller. I had initially planned to have the cylinder in the utility room close to the ASHP Monobloc, but changed the location to a service cupboard in the middle of the house, to reduce internal DHW pipe runs. This does mean a 15 metre pipe run for flow and return to the ASHP, but as virtually all is within the insulated envelope, it doesn’t represent much of an issue, and does not appear to be having an adverse effect on performance. The ASHP Monobloc itself is located beside our back door, open to the elements. It seems happy enough where it is, despite the wind that traverses the space between house and garage walls. Locating the ASHP within the garage itself was an option but one I decided against simply on the grounds that I didn’t want to give up floor space within the garage. A timber housing for the ASHP is something we may look at in the future. We opted to fit individual room thermostats to all 3 bedrooms, to give us the option of being able to reduce the bedroom temperatures if we so wished. We have not used these and keep the whole house at one temperature 24/7, treating the underfloor heating as a single zone. At present I only have limited data as to how the heat pump has performed since moving in. On board energy metering (energy consumed and energy produced) shows the CoP for heating has ranged between 3.5 and 4. DHW is maintained at 47C-50C in the cylinder, boosted every fortnight to 60 degrees by the immersion on an anti-legionella cycle. To date the CoP for DHW is 2.4 As members know, heat pumps are best suited to the production of low temperature heat as opposed to the higher temperatures required for domestic hot water. Whilst the CoP for DHW is lower than that for heating, the cost per kWh of our DHW, based on a CoP of 2.4, is 5p, which is significantly better than an E7 electricity tariff. We may be taking a hit on efficiency, but in reality all of the other options would have cost us more. The 300 litre capacity of the cylinder means that we have plenty of hot water on tap and can comfortably run a full bath and still have sufficient left over for another person to shower. The ASHP is currently operating on a 24/7 basis, providing heat input to the UFH and topping off the DHW as and when it determines it needs to, at whatever flow temperature it determines. Whilst that does sound like a recipe for high bills and high flow temperatures, in practice, the heat pump delivers the lowest flow temp it can get away with to maintain our set temperature. If I so choose, the controller lets me set various parameters such as heating curves or set flow temperatures, or indeed a timed schedule for heating and DHW. However,as the system is operating efficiently on its auto setting, and providing the level of comfort we want, I see very little reason to mess around and create my own settings. If say electricity tariffs were to change from a single tariff to a dynamic tariff, then I would have the option of timing the heat pump operation to coincide with lower rate tariffs. After much thought, and indeed discussion on this forum, I opted for an 8.5 kWh ASHP over a 5 kWh ASHP, as I felt happier running a larger unit more gently than pushing a smaller capacity unit harder. A 5 kWh unit would probably have sufficed, and in time, may be what the current unit is replaced with when it reaches the end of its life. We haven’t yet had to activate the cooling function as any overheating (defined as internal temperatures over 23C) caused by solar gain, can, as modeled, be managed by natural cross ventilation. Neither have we found it necessary to constantly circulate the UFH to even out the house temperature / redistribute solar gain from one part of the house to the other. In the heating season, we found that there was sufficient circulation of the UFH during the heating cycle to maintain the house at an even temperature. Outwith the heating season, when solar gain is at its peak, the house zones itself, the bedroom section remaining slightly cooler than the public areas, very useful on a warm summers day. Overall I’m very happy and impressed with our system. It has, so far, delivered everything we have asked of it in terms of comfort and convenience, and the running costs are low. I have the capability to cool the house (via slab cooling) if I so wish, and the option to bolt on a second zone pack onto the pre-plumb cylinder if I ever found it necessary to install a second heating / cooling function – i.e. fan coil or duct heater / cooler. The one criticism that I have is about the controller thermostat function and its hysteresis - 1C increments only. A finer degree of control would have been preferable. Our installation was recently inspected by an MCS accreditor (our plumber is going through the accreditation process). In due course that will give us the option to apply for RHI, although that will be very much dependant on whether the figures stack up.
  25. I only got to use my UFH for a month at the beginning of the year when @Nickfromwales and @PeterW fixed it for me as it's been switched off for summer ever since. Now that I've switched it back on in 2 rooms I thought I had better try to understand how it operates a bit more. So first questions: On the TS there are 2 cylinder stats. The top one is set to 65C and the bottom one to 45C. When a room calls for heat what determines whether the boiler switches on? The bottom cylinder stat at 45C? And when it gets to 45C the boiler switches off? And if the hot water is switched on I assume the boiler will stay on until the top cylinder stat is at 65C or the time stops? So the cylinder stats are for different purposes and work independently? Last night it took a fair while for the temp to rise from 17C to 20C and the boiler kicked out 37kw over the course of last night and first thing this morning. Maybe I should have expected this the first time the slab has had to heat up this year however .... This morning when I got up it was at 20C and it hasn't dropped at all today so the heating hasn't come on yet tonight which is a good thing I guess. It hasn't been baltic outside today however. Will be interesting to see how much it drops when it's colder.