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I really don't understand where this MVHR mandatory 'sealed box' perception comes from. It's all about giving you options, not imposing anything. Our house is passive standard with full MVHR and we open doors, sliders and windows year round as we please. The point is we don't have to open doors and windows to get fresh air or expel stale air as the MVHR is always taking care of that. But we can if we want, at the small cost of energy efficiency (i.e. re-heating the warm air that has escaped in winter). N.B. if you open a single door or window then as the rest of our house is airtight then there is little air movement you need to open two to get a cross draught. Actually being able to keep doors & windows closed is most useful in summer. At night we open one slider a crack (in a locked position) and open the Velux at the top of the house - cools everything down nicely. During the day we try and keep everything shut to minimise warm air from outside making the house uncomfortable. We don't have an active cooling system like some here (air or slab) so really need to watch overheating in summer. Even if every door and window is open, the MVHR extract will still work fine - you just loose some efficiency on the heat recovery side. You can configure the system to do what you want - most of us here have balanced it and figured out how to meet BR standards and then dialled it back down to a comfort level. For us this is 30% fan for comfort and 50% for boost. We have PIR sensors in each bathroom which trigger the boost mode, also triggers when a bathroom light is turned on (and doubles up as the trigger for the DHW re-circulation pump).

It's the overflow pipe from the brine tank. It won't normally have anything flowing through it, and can be plumbed to a drain, rather than out through the wall (ours is plumbed to a drain, well above the connection from the normal drain pipe to the same drain).

Now that I am partly retired, I will begin my dream project: starting a new build once the bungalow which I am in the process of buying is complete, then will move to the next phase of PP. The bungalow came with PP but the design was not to our liking, so back to the drawing board for a new PP. As a newbie I will definitely need all the help from forum members. We have decided on a highly efficient energy house like Passivhaus but will not go for PH certification too costly!! A passive Timberframe with an insulated slab with triple glazed windows, MVHR.

Most building merchants can supply. Get a few quotes as it's purchase worth shopping around for. I used CUPA 3 heavies, got them from Jewsons. Might be worth having a look on my roofing entry on my blog. Don't forget your slates and half.

Dunno...I will say that Sikaflex I think skins up quicker than CT1... Sikaflex I think goes off more solid that CT1 though it still has a resilience about it.

Google found.. https://cableductuk.com/700series.html?gclid=Cj0KCQjwpLfzBRCRARIsAHuj6qUTH6BdbeW5nGHVzZkM3BUnj4kD9oj_oCCIZok8hdaCzextaqjpfcMaAvFBEALw_wcB

I used these wing screws. Did have to countersink the ply from memory. They went in a treat. https://www.screwfix.com/p/easydrive-carbon-steel-self-drilling-roofing-screws-4-8-x-38mm-200-pack/2688h

I Sikaflex'd 9mm ply onto my frame. I had to add a 9mm layer to ensure the subsequent Aqua Panels cleared the soil pipe at the base of the wall. Pretty sure that adds to keeping the frame in place. I used self drill screws through the ply into the Geberit frame. I was really careful to draw the frame on the ply so I didn't drill into any pipe or God forbid the cistern! Aqua Panel again Sikaflex'd to the ply: Again I marked a red zone where I daren't have drilled! The self drill screws were no good for screwing the Aqua panel through the ply and into the metal frame. I just used the proper Knauf screws where there was timber behind.

Yes, we have an F7 filter on the intake to ours, which filters out pollen and a fair bit of the smaller particulates (takes out about 70% of PM2.5s). A useful benefit if you suffer from hay fever (as I do). It means that I can go for days in the pollen season without needing antihistamines, which is a definite plus. Ours was audible initially, but fitting silencers fixed that. I'd recommend fitting the biggest silencers you can, as they really do make a big difference.

To see a blockage before have set phone to video with flash then held it down near invert. You might see the connection 4ft away or something like that

As above its futher downstream then. Dig downstream of the IC

There seems to be two inspection covers in the photo. I wonder if the loo is connecting further down to the second one? Might explain why you can hear it but not see it. It also looks as if the invert is a lot deeper than the hole you've dug, so the chances are that the pipe will be a fair way down.

That doesn’t make sense .... You are flushing the toilet but it’s not coming through that manhole ..? If that is the case, you have a good chance there is a further pipe running at 45 degrees to the house and joining further along. My guess would be that could well be a rainwater sewer and if you pour a bucket down the gully that your red line goes through it will come down that pipe. Can’t connect a toilet to that.

Undo tighten the legs with a 13mm socket or spanner. I put coach screws in the side of the frame: As for not using the top, main fixings... You could glue & screw some timber blocks to the uprights and use studding. Might need to counter bore the blocks with a flat wood bit to take the nuts. Double nut it too so it doesn't come undone. As for the pan security...once tiled put it on the wall with clear CT1 backing up the fixings and leave for 36hrs.

@Delicatedave can't fault mine. It's the compound mitre saw with the 230mm blade I think. I've even swapped the blade for a diamond stone cutting blade for cutting tiles and coping stones. Cost me about £80 a few years ago. I see the prices have gone up tho.

A further benefit Also, if you are sensitive to pollen etc then you can get higher grade filters to trap this. Downsides of MVHR - running cost :should be minimal but they're not free to run - noise : If not properly located, the larger units can give off vibration noise and you may get a slight drone through supply vents, although these can be minimised by incorporating a silencer. - maintenance : the filters do need regular cleaning and occasional replacement and the heat exchanger benefits from a good clean twice a year. - installation: can be fiddly getting the duct from each room back to the manifold / MVHR location and you need to consider how to get the larger bore insulated ducts from the MVHR to an outside wall or use roof vents. Good design early on will minimise the installation complexity and it's definitely something you can DIY and save a few grand on installation. Keeping the unit central will equalise duct runs and make it easier to balance the system but this is not always practical. Ours is in basement plant room on one side of the house and works fine.

I agree with all above and whilst planning our MVHR asked if it was possible to have it running only when the air was stale but this is more trouble than it’s worth. For “boost” I have a humidity stat mounted in the exhaust manifold, I can set the RH level at which it comes on (Bath, shower, cooking) and when the level gets back to a set normal it simply switches off. For the very small amount it costs to run it might as well stay on, but you could always switch it off during fine weather. Just had a thought, if you switched off (by having a switch to the trickle setting) it would still come on fir boost if you wanted it too. (I might do this myself).

Popping the inspection cover will also give you an idea of the invert, which in turn will give a good feel for how deep the pipe is. Could be a fair way down.

Did you pop the lid on that manhole cover to see if it's coming in straight or at an angle?? If you can get some one to tap the pipe at the toilet with you holding your hand on the dug out section you might feel some vibrations.

Floor sockets come in 2 basic sorts. These, https://www.tlc-direct.co.uk/Products/FP9UPCW.html that fit a standard back box. but don't seem to be available with USB and are a trip hazard in use. Or these https://www.screwfix.com/p/schneider-electric-standard-3-compartment-floorbox/67628 which ar used a lot in offices. They are much larger and need to be set in the floor, but you can put anything in there and then shut the lid with stuff plugged in and just the flexes emerging. They are usually intended to have carpet inset into the lid so may not work well if you don't want a carpeted room.

And to add there is noting to stop you opening doors and windows in the summer. MVHR does not preclude that. A side effect of a well sealed house with mvhr is even on a windy day, you can open one door or one window and not get a howling gale blow through from all the uncontrolled ventilation openings you have to have in a non mvhr house. P.S our house does not feel like a sealed up tupperware box.

+1 to both the above ^^^ MVHR gives you very good air quality, and reduces the heating requirement, on days when you want to keep the doors and windows closed, because of the weather outside. If you want to open the doors and windows when the weather's fine then just do so. Our MVHR just provides background ventilation to keep the air in the house fresh all the time, and will boost up to a higher rate when it senses that the extract air is more humid, usually when we running a shower or when cooking. If we wish, we can just press the boost button, each press puts it in boost mode for an hour, so three quick presses gives three hours of boost. The house never has any condensation anywhere, clothes dry very quickly if just hung of the airer in the utility room (no need to boost to get that to happen), the house needs a lot less cleaning, as all the fresh air is filtered, and we don't have any spiders or flies in the house.

+1 to everything @Bitpipe has said. We have installed MVHR in a number of houses, the first was a standard regs build back in 2003. Leaky, poorly insulated in comparison to today, yet the difference it made to air quality inside the house, i.e. constant fresh pre warmed controlled flow air (rather than howling gales through trickle vents) and the elimination of condensation made it a must have for us irrespective of any cost savings on heating bills.

Could be a pressure relief overflow

They come with a phosphate dosing filter to reduce the build up of limescale, or at least ours did.

Saw this yesterday whilst I was festering in my anger, made me smile - like everyone going through this, quitting ain't an option.

A compromise ! Took some plastic black pipe to builders merchants . Bought a new brown pipe coupler that also fits the black . So ; a compromise was born ! ; just the black coupler exposed externally.

No it's about 20 W all the time that it's switched on. We have it on a time switch, so it comes on early in the morning and turns off in the evening. Off the top of my head I think it's set to be on for about 15 hours a day, so roughly 300 Wh/day for the "keep hot" energy requirement, plus a bit used to heat from cold, or reheat after a cup, or saucepan, of hot water is drawn off. When re-heating it uses around 1.5 kW, and takes a minute or two to get back up to temperature after a cup of tea has been made. For much of the day the 20 W will come from the PV system, so I'd guess we're only paying for maybe 150 Wh/day for the "keep hot", plus maybe another 300 Wh or so per day for the re-heat energy. All told it might cost around 7p or 8p per day to run. It probably saves a fair bit of energy overall, as we often use the boiling water to cook vegetables, saving energy that would otherwise come from the hob. It's also economical in terms of the amount of boiling water used for a cup of tea, as it's only ever re-heating the cupful that's been drawn, rather than a cupful plus a bit extra in a kettle.

I have a 1000kg scissor lift on mine at the moment.

You can load out a beam and block floor that has where you just brush in a lean mix grout. The concrete would give added strength but you should be OK. The supplier should advise on max loadings. I have seen one fail but they had staked blocks 2 packs high x 2 along one beam and the floor had not been grouted.

If you can't concrete it now how about a large thick tarp? Put some blocks on it to stop it blowing away.

Updated setup. Others have the Willis with element at top, but I may 'lay' mine down to prevent air being blocked in top. Will see what the instructions say, if anything. Internet a bit scant on instructions so will post on here when I get the goods. Also added bottle vent to manifold and NRV on mains fill line. Apologies for the small print.

I’m getting to the point when I need to start looking at all the stuff to go inside the house, yes I know I should have done this a year ago. Anyway let’s talk mvhr so I fully understand that standard extraction systems are going to take the warm air out of the house and waste it by blowing it outside and I understand the principle of using the warm air to heat the incoming fresh air. What i I am having problems with is getting a grip on how to get a good system to work with our lifestyle we don’t want to live in a sealed up Tupperware box, I have read so many comments on how quite there new house is and I fully agree now our windows are in its silent in side, so I know what that means come May- June the kitchen window will be open and also the back door, the door will be open to let the dogs run in and out and the windows will be open so the wife can hear the birds as she bakes a cake in the kitchen. So how do we make this situation work, i want. Good extraction from wet rooms good extraction from laundry room good extraction from kitchen extractor. Is there a system that will sit in very very low mode and boost up when you enter the bathroom, or a boost switch in the laundry for when the back door is shut. Do you think Hinks mvhr is right for us or do we look at alternatives, confused as usual i much prefer just digging holes.

Litter tray!