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Found 86 results

  1. Following on form the PHPP calls it looks like we'd benefit from some active cooling. I know Jeremy has the Genvex Premium 1 and is very happy with it, but are there any others out there worth considering? The only other that I've seen so far is the Paul/Zehnder one but that's coming out at about £7.5k plus vat - the Genvex Premium 2 that we'd need is about £5k from Denmark and £5.5k from the UK (both plus vat). I'd obviously like to get that down as much as possible if I can
  2. Hi All, I hope you're keeping well! I just wanted to introduce myself 'Joe' to the forum as I have been a long time reader and now hopefully getting closer to starting my own build. The forum is such a great resource for information and the knowledge of the users is simply amazing - I really do appreciate everything I have read here as it has helped me so far on my journey. I am hoping to learn as I go and all being well, I'll be able to help others as I pass through each stage of the build and gain my own knowledge and experiences. The house is a two story house with a connection to single story building for the kitchen, dinning and living area which in total is approx 330m2 sitting on 0.8 of an acre. It will have a ground source heat pump, with underfloor heating on the ground and first floor, mechanical ventilation heat recovery system and a PV solar array with battery. Windows triple glazed throughout. The current SAP report SAP rating: 92 A Environmental: 93 A If I have missed anything I will update the above. All the best, Joe
  3. Hi, we've just bought a house that has a very old MVHR installed which needs the main unit replacing and the ducts cleaned and balanced. We are not planning on having an airtight house and will keep windows open during warmer months. We cannot decide if the benefits of running an MVHR in a non-airtight house warrant the cost to upgrade/service. We cannot find anyone in the local area (North East) that can assess our installation and make recommendations so would be grateful for your opinions. The installation is very old, the main unit is branded "Flow Engineering" and I've attached some photos. I can hear the fans are working but I cannot feel any air movement through the vents. There is galvanised metal ducting to every room and it extracts from kitchen, utility and bathrooms. The unit is mounted in the loft and there is no loft insulation at all. Is it worth upgrading and servicing the MVHR system or would it make more sense to install an MEV with the existing extraction ducting and remove the rest of the ducting in favour of loft insulation?
  4. I'm still trying to figure out how to best combine a regular MVHR with an add-on to provide for additional heating/cooling if required and have come across the Mitsubishi Lossnay system that includes the option of adding a GUG Air Processing unit (datasheet attached) that can combine with a small ASHP to provide direct heating or cooling of the supply air. I'm guessing this unit could be added to any MVHR provided the system had been designed in the first place to allow for increased volumes of air flow to move hot/cold air around to achieve an effective cooling/heating effect. Has anybody any experience of such a system in a domestic house setting? Or is this kind of set-up mainly used for commercial buildings? GUG-010203SL-E_PI_SHEET.pdf
  5. Hi there. This is my first post on the buildhub. I'm a halfways capable DIY-er, with more mistakes behind me than successes, but I learn. My current problem is the ventilation of my sons' bedrooms. Do you think you can help please? The window in each room has no trickle vent. Please see the attached photos. I do have a sliding vent above each bedroom into the hall. With 3 boys sharing two rooms, a lot of moisture and smell is generated overnight. I am not keen on leaving the windows open overnight, due to draughts and security. After watching a DIY video explaining how to retro-fit a trickle vent in a DG window, I drilled a pilot hole in one window frame, expecting a short penetration into void space within the frame that could likewise be accessed from the other side. Instead I hit something solid - possibly metal reinforcement within the frame. Anyways it looks like trickle vents are out, unless you can advise on what I might be doing wrong with the window frame, or perhaps suggest another means, e.g. through the brick wall? I'm concerned in any case these vents are passive and largely uncontrollable. They are also subject to clogging and the effects of wind and other weather stuff. Buildhub led me to the idea of PIV. I have plenty accessible space in my loft and easy access to gable ends, but not much money. I suspect they are expensive? I have two bathrooms, a kitchen and a living room, as well as 3 bedrooms to be involved in PIV. Do you think that might be a solution? What are the limitations? Can I DIY the installation? I also read about MVHR. Do you think that could work? Again, I don't have much money, what are the limitations? Can I DIY the installation? I read that this solution is dependent on air tightness levels of 5ach or below (air changes per hour). No idea how I can measure that. Do you know? A few questions here. Apologies. I hope you can provide some good advice that will help me. Ay. James.
  6. Hi all Would love to get your views on this. We're upgrading our early 1970s detached house, with (as a minimum) cavity wall insulation, insulating under the suspended floor, upping the loft insulation and replacing doors and windows with triple glazing (Rationel / IdealCombi / Norrsken TBC). We may also insulate walls externally (subject to cost / budget). We're also building a kitchen extension which will be heavily insulated and airtight. We're now looking in to installing either a MEV or MVHR system. We've got supply only quotes from BPC of £2150 for MVHR and £575 for MEV, with extract from 3 bathrooms (upstairs, downstairs and en-suite) and the kitchen. We've got a young family and both work pretty much full time, so we're only really in the house at weekends and evenings. In summer / warm spring days the doors into the garden will be open, so lots of air will be drawn into the house. I know there's the thinking that MEV is throwing away money, extracting warmed air, but surely it would take a long a time for this to add up to the £1500 difference in supply cost, plus probably that again in installation cost. Heating is standard central heating from a combi boiler. My current thinking is that MEV would give the benefits of quiet extraction of moisture and odours from the bathrooms and kitchens and avoid the need for wall extractor fans, and its hard to justify the additional benefits of MVHR given our use of the house. It would be really good to hear from anyone who has a MEV system installed, or who upgraded from MEV to MVHR. Thanks!
  7. Hi guys, Wondering if anyone with experience of MVHR in new builds can advise me on a few things. Essentially I'm working on my self-build and I'm just wanting to make sure I'm correct about some of the building regulations regarding the installation of MVHR. So the house will have the following dimensions: Basement area - 210m2 (504m3) Ground floor - 210m2 (504m3) First floor - 135m2 (324m3) Second floor - 135m2 (250m3) Total 690m2 (1588m3) Some additional info is that there are potentially 7 bedrooms, 1 kitchen, 1 utility and 7 bathrooms. The number of occupants on a daily basis will be 4, however we will likely have up to 10 people total staying in the house at any one time. Now my questions were regarding the size of the MVHR I need to spec. I understand that according to building regs, the rate of exchange should be a minimum of 0.3l/s/m2, which based on my 690m2 of space gives me a system that can handle 207l/s (745m3/hr). Firstly, can anyone confirm that I have understood this properly? And then my second question is that whilst we do have a large space, the number of inhabitants most of the time won't be particularly high and some of the spaces, eg loft and basement space, won't be used on a daily basis - so would I be able to get away with using a system that just passes building regs (eg. one that can cope with say 800m3/hr - Daikin Air Conditioning Ducted Heat Exchanger VAM800J; or Lg Air Conditioning Eco V Heat Recovery Ventilator LZ-H080GBA5; or potentially a couple of the ), or would I need a system with a much higher potential capacity (eg ~1000-1500m3/hr - eg the LG heat recovery ventilator LZ-H150GBA5)? Was hoping those of you that own MHVR's and have experience using them can help me advise me as to whether Building regs requirements are over the top and in reality the system wouldn't need to work anywhere near as hard to meet our needs. Also if anyone has any suggestions with any particular brand or heat exchanger then please feel free to recommend. I've explored the options from Titon and Zehnder but it seems I would need two of their systems to cope with the floor space - putting us at ~£4.5k for the systems; whilst the ones I've suggested above are approximately half of that so whilst they have a slightly lower efficiency (80%) I figured the extra for the Zehnders wouldn't be worth the time it would take to recover the extra £2-2.5k. Opinions welcome though! :) Thank you in advance
  8. Do I actually need someone like BPC to design my MVHR ducting system? For my new-build bungalow, it seems really simple. I have designed the ducting plan myself following the basic rules: equal number of supply and extracts across the house (5x of each) double pipes to every terminal so it is quiet supply to bedrooms and living room (x3 & x2) extract from bathrooms, kitchen, utility room and plant room (x2, x1, x1, x1) room terminals as far from the door as possible Seems simple! What am I missing? Is a pro-design for the air-change data, which is needed for building control? The reason I am thinking about this now is that I am just about to put the timber-frame in to production. The frame has one single structural steel. And that steel would benefit from some pre-cut holes (x6) to allow the 75mm MVHR ducting to pass through it. I can cut the holes based on my design. Or should I get a professional involved?
  9. I'm planning on installing some sort of ventilation to the upstairs of our house, not sure if MVHR is worth it. The reason for wanting it is just for ventilation, I seem to sleep better with the window open as long as there’s a bit of a breeze to move the air around, but the bedroom window is at the front of the house so there’s a lot of road noise in the mornings. The bedroom humidity gets high overnight, and we get condensation on the window most mornings if it’s closed. We also have an en suite with no extractor fan and the main bathroom extractor fan has stopped working too. The house was built around 2008 and not air tight etc, but as I’m planning on doing something to the ventilation anyway it feels like saving some heat is better than nothing, and I just like the idea of MVHR. It would probably be cheaper to just get two new humidity controlled extractor fans for the en suite and bathroom, and some sort of ducted ventilation for the bedroom. I really don’t know how efficient an MVHR system would be in this situation as I have no idea what the air tightness level of the house is, although given there is an open fireplace downstairs it probably is quite low. Any advice on how useful it would be? And if so what system to go for, I can find a Vent Axia HR100R for just 280 euros, has anyone got any experience with these?
  10. Question is, do I need fire rated MVHR valves anywhere? I can't discern it from Approved Document B, but I guess it's in there. I can't find the answer here, but I guess it's probably here as well somewhere. I asked my BCO a while ago, he didn't reply. Before I try him again, I'd like to know. Is there a simple answer? Do we or don't we? Are there rules of thumb?
  11. Morning, Is anyone able to recommend an MVHR installer in Cornwall or the SW please? Many thanks, Jenny
  12. As you know we have just moved in and it is a steep learning curve with all things ASHP and MVHR. When it was freezing on xmas day I noticed the casing on the Vent Axia Sentinel was dripping slightly. I checked the controller and it was flashing anti-frost. With it being xmas day I just turned it off for now but just wondered is this the norm for it to drip? Have I not got enough slope when I fitted as I assume this is what the condensate drain is for? I wrapped the inlet/outlet pipes in armaflex and then the flexible pipe insulation from BPC so all should be ok there. Have people come across this before and if so what did you do please? I am trying to come down from the exertions of the last month of trying to get in the new house before xmas and my head is a complete mash of new tech and mundane issues that need sorting. TIA
  13. Hello, We are building an end-terrace house. Its a 2 bed house with living space and kitchen on the ground, one bedroom on the first floor and one on second (loft conversion). The house has 2 x high voids from ground floor to the 2nd floor ceiling (sloping roof in the front and flat roof at the back). It was struggle to get our fire strategy approved, but we finally have it approved too. At present, we are building the concrete slabs and beams and bricks are on site. We have decided to hire Stroma for environmental checks who will initiate their works soon. Being a tech guy, I am too keen on having an eco-friendly house and feel fitting an MVHR will bring lots of benefits in terms of heat recovery, fresh air, more oxygen, etc. But am concerned on the requirements of having too many ducts and vents. Please feel free to answer on these questions for me to move more towards a firm decision: 1. To avoid having too many ducts running across the floor, can we fit the entire system on a single side-wall with all wall vents in the bathrooms and rooms at all levels? i.e. can we have a complete system without a ceiling vent? In worst case, we can have vents in the roof, but feel it will need a lot of ducts. 2. Would be be feasible to fit the main unit on ground floor? 3. What will be vastest cost effective small sized system which can send in oxygenated/healthy air and also have cooling functionality? Thanks, P
  14. We have four pieces of foam with our Vent Axia sentinel and there are no instructions as to what they are for. I assume they are to be fitted on the back of the unit for sound deadening although the gap to the rear of the unit is greater than the foam? TIA
  15. We have a Vent Axia MVHR and are currently fitting the unit and associated metal ducts. The drawing from BPC specifies the silencer to be mounted vertically. No space for that in current position. Can this silencer be mounted horizontally please?
  16. Hi, I spotted an opportunity to save money a while back and in areas where we are not using the space all the way to the roof I changed from PIR insulation between the rafters to rockwool above the ceiling. What I did not realise though was that the MVHR ducting has to be in an insulated space. So now we need to insulate the MCHR which loses almost the entire saving. The installers have recommended using 50mm foil backed insulation wrapped around the ducts. This is fine, but I wondered if in areas where the ducts are installed just above the roof trusses and the loft insulation was pushed under the duct work could be just add another layer of rockwool that covers the duct work? This would be a lot faster and cheaper, but there is more risk that bits of the duct aren't covered.
  17. We are trying to do our best to create a pretty airtight house.... Our Architect has suggested a joiner made front door. Will this be a huge source of air leakage? We are installing MVHR and ASHP and it will kill performance if the door lets wind through. Our current double glazed french patio doors let a gale blow through on windy days....
  18. Hi everyone! We are at the foundation stages of a newbuild. It's a replacement dwelling for a chalet bungalow in the centre of Marlow, Buckinghamshire. Very keen to read about other projects and get some advice on ours. Cheers, Steve 3_Westwood_Road_Design_&_Access.pdf
  19. Left this a bit late and BPC shut for the day. I need to build my external block wall tomorrow on the exterior of the timber frame. I will have to put 3 pipes in the wall to take the flow/return and power for the ASHP so I can seal them from the outside to the frame. I am proposing to use 50mm pipe for the wet pipes to leave enough room to insulate round the pipes afterwards (Passive) and 20mm duct for the power, does this sound ok or would people use smaller pipes? Do not know make of ASHP yet so do not know if I will need 28mm or 22mm pipes. How close can the ASHP be sited next to MVHR vents? I have a low level vent, approx 500mm off the floor and one at 2.2m and they are 1.5m apart and cannot anywhere else. TIA
  20. Hi everyone, I'd like your help pls. We're self building a new home and are installing an MVHR system. It's on a hill and therefore an upside down house; so bedrooms on the ground floor with bathrooms/plant room while the living room/office/kitchen are upstairs on the first floor. We have web joists and I was wondering about putting the outlet vents to the living room and office coming out of the floor of these rooms since this is much simpler. The duct to these would therefore be on the same level/branching as the ceiling ones that feed the bedrooms on the ground floor. So they would all run through the space between the two floors rather than having to run the ducts up the first floor walls and across their ceilings as well. Hope that makes sense? I've tried searching the forum and can only find a few references to a German floor vent brand. Is it better to do this? or are there any major downsides pls? Many thanks Iain
  21. I’ve just spent most of last week installing the distribution boxes, ducting and plenums on my BPC/Vent Axia system. I thought it would be worthwhile sharing some pictures, It went well and was relatively easy to do. I tried to keep ducting passing over each other in the joists to a minimum but it was unavoidable in some places. Having two ducts on top of each other in a web joist was a bit tight and didn’t leave a lot of room for insulation. I had already installed the 150mm PVC pipe through the roof and drilled a 150mm hole for the second PVC pipe through the wall. I then mounted the Vent Axia unit on the wall and figured out where to mount the distribution boxes in the metal web joists between the ground and first floors. We have vaulted ceilings upstairs so it seemed easiest to mount the boxes here rather than up high in the first floor. Here’s my rough in of the MVHR unit. Ignore the angles of the pipes. These will be straightened up on the final fix. Here are the distribution boxes. Required careful planning and it didn’t seem to matter where they were because of the metal web joists there was always at least one duct which was a tight squeeze through the joists. I have a change in levels between the main part of the house and the lower level which causes a bit of head scratching as to how the get the ducts from one section to another. This was exacerbated by the fact that there was a steel running across the lower level which I had to navigate around. I built a dummy stud wall in the lower level and ran the ducts behind this. I need to get 3 extract and 2 supply ducts into the lower level. Here’s a photo after the first 4 ducts were run. A bit of boxing in required to hide them, but relatively easy solution. and here’s what it looks like in the lower level. And finally, a ceiling mounted and wall mounted plenum. I quite enjoyed doing it and it was satisfying to see it all done.
  22. Has anybody had any experience of this product from BPC ? TIA
  23. How do I find out if I need fire rated terminals for my MVHR ducts. Is there some guidance written in stone or is it down to the whims of Building Control (who aren't answering my questions at the moment). Do you have to have them in the kitchen for example but not bathrooms? Any guidance would be much appreciated.
  24. Hi I'm looking for advice from anyone that has a Itho (Heatrae Sadia) Hru Eco 4 fitted in their home? We moved into a property in 2018 with 2 units (dating from 2010), both were serviced last year but we recently noticed that the discharge fan in one of them is no longer running smoothly and as a result, creating more noise and subsequent lack of air flow through the ducts. We ordered a new fan but we have exactly the same issue - the fan sounds like it struggling to maintain a constant speed. Any thoughts? We're trying to find an engineer who can come and look at it at the moment but no luck so far! TIA
  25. So finally everything is in place: * mvhr unit up and running * terminals and valves installed * house pretty much as air tight as it will ever be * Anemometer Tesla 405 borrowed with extra large valve covers - big thanks @JSHarris So to work on balancing. Any tips on how best to approach this? * Screw everything shut and open on longest extract one first get its flow rate right and then open another set it and go back to first readjust? * Set all valves at middleish point and randomly run around house? * Concentrate on extract first? Concentrate on fresh air first? pick and mix? Any other tips? * Place chairs under every valve before starting? * Get 5 tall mates from the pub? * wack the unit up to max and slowly decrease? * count the number of turns needed to add/remove 1litre/sec? Bit concerned this could take all day and night if I just run around the house randomly with the meter! Thanks in advance, Paul