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The problem with the investment in battery technology (if it is a problem) is that all the money has gone into producing very light, energy-dense, battery technologies, mostly using the lithium ion exchange mechanism. This is what electric vehicles need, both a high energy density and a high power density. Electric vehicles don't really care too much about cycle life, as with a range of >200 miles per charge only a small number of electric cars will need more than around 1000 cycles before the rest of the car falls to bits from old age (200 miles per cycle and 1000 cycles gives a life of around 200,000 miles, more than most cars will ever need). Either home energy storage (which makes sense in terms of grid efficiency for homes that have renewable generation to spare at peak times) or centralised grid energy storage needs a much longer cycle life to be viable. Batteries will be cycled at least once per day, possibly several times per day for a peak-lopping grid storage system. The types of lithium cell technology that have been getting massive amounts of development funding isn't really the ideal technology for this, as weight and size aren't major issues for fixed storage, neither is peak discharge rate (home storage probably doesn't even need a 1C discharge capacity, unlike electric cars that may well need a peak capability of 10 to 20C). There are a few technologies that make a lot more sense for grid storage, and one of my favourites is the redox flow battery. Cycle life for this type of cell is pretty much infinite, but they do take up a fair volume for a given capacity. Some research is being done, but there just doesn't seem to be the high level of development investment that, say, Tesla have put in with their battery partners, Panasonic/Sanyo. Similarly, the one type of lithium chemistry cell that does have a cycle life of around 10,000 to 20,000 cycles if managed carefully, LiFePO4, has had very little development over the past ten years or so, because it has a relatively poor energy density, and this makes it less well suited to electric vehicles.

I own both and agree that the air nailer is by far more reliable. But there is no chance you would catch me taking it up on a roof. Also if I can avoid that poxy compressor running all day I will. As for the gas, just keep a spare in your pocket. Firstly it keeps it warm and secondly it gives a very impressive bulge...

Thought you were certified already ?

Well that's the 18th passed today. Now if I could only blow my own trumpet...

At 10pm last night I was about to cut a hole in the only working foul drain on site to fit a boss and merge in the grey water drainage from the static caravan. Then I thought if I get this wrong it is back to bucket & chuck-it in the morning. I put my drill down, called it a day and slept well.

Our design calls for some pocket doors - 6 in total - good for space saving, should look tidy. We decided to go with Eclisse and got them from the ever helpful Alan at Door Supplies Online. We will also get our door sets from him, to match, and he'll supply some matching architrave to finish the pocket doors nicely. Will post photos of the finished doors when we get there (probably September). In the meantime, we needed to install the pocket frames in advance of plaster boarding. It seemed too easy. But I am posting this because we had slight issues understanding how they fitted so hopefully this post will help someone else in the future. Him indoors built them so quickly I didn't even get photos of him putting them together. But he assures me that the instructions were straightforward to follow and they went together well. Top tip - don't throw out the bits of polystyrene that look like packaging. They actually help give it some bracing strength when lifting the whole thing into place (otherwise it bends quite a bit). The You Tube videos are also helpful. Our MBC structural openings were exact (to the mm) so we had allowed a bit too much structural opening (we didn't know how mm perfect they would be). We then had to pack slightly off the stud frame (offcuts of egger board and OSB). And also pack off the floor to ensure the door was fitted at finished floor level. Have allowed 20mm for carpet / underlay upstairs (and tiles to the bathrooms) so should be OK. The frames come in 100mm finished wall depth or 125mm finished wall depth. With 89mm stud walls this does give a bit of a conundrum, assuming 12.5mm plasterboard. We chose 125mm. And then Alan suggested putting ply on the frame as well to make it extra rigid. Also useful for subsequent hanging of pictures / toilet roll holders on finished wall - otherwise fixings might go through and result in scratching the sliding door. What we couldn't understand was that the pocket side of the door had a frame that was 125mm wide. But the bit the door closes on was only 100mm wide. For a short while I doubted the assembling ability of my definitely better half. Thankfully, a call to Alan set that straight. Though I am not sure I have been forgiven yet. There is a timber jamb (125mm wide) that fits over the 100mm section, making the whole thing 125mm wide. Now for the ply. It has been a bit of a juggle. Some need ply and some don't, some need double ply before plasterboard on one side to build out the stud work. And we need to match the ply on each side otherwise the door will be off centre in the total wall depth. Feels like overkill and probably is. But it will be solid! The ply attaches to the door frame itself using little screws (supplied by Eclisse). If you don't put ply on then these little screws fix the plasterboard. This door below has ply on the left hand side to bring the stud wall out to the frame edge. Then it will have ply over the top of that (and the frame) to match the other side. Then plasterboard. Toilet roll holder going on the other side and mirror on this side so will be strong enough for those. From the inside of the en-suite it looks like this, with one layer of ply. So, just plasterboard over the top of this. All the standard (classic) pockets are now fitted. Ply to go on the other 4 still so plenty of late nights in store before the plasterboarders come in. We are rather enjoying this bit though. Allows us to actually contribute to our build in a meaningful way, saves some cash, justifies the circular saw Christmas gift...... The telescopic pocket door is being saved for another day.

Exactly, worse for whom? For those lucky enough to be in the ladder and worried about a hit on values? Or worse for those who can't get in it's because of inflated prices? Whoever its worse for surely that means it's better for someone else?

I guess the order will vary from build to build as to what's the 'best' order, but this is how it happened for mine: 1. Engaged and commissioned architect with a relatively detailed brief of how we wanted the house to function for us. 2. Whilst waiting for PP: decided what type of build we wanted, researched TF and slab main contractors, decided on main contractor (subject to satisfactory quote) 3. Immediately after PP, engaged TF/slab main contractor and M&E consultant. 4. Commissioned architect to do building regs drawings. 5. Architect, TF/slab supplier and M&E consultant worked together to make sure that the house could be built as conceived and that the systems would go into the building. Thinking here about ensuring space for plant and equipment early on and things like penetrations through steel beams where MVHR ducts would need to run. 6. Had a soil survey done, indentified need for piles on site due to clay. 7. Engaged SE for piles but didn't use their advice in the end, for 2 reasons. Their initial proposed solution was too expensive and, in the end, the piling company had their own SE who did the calculations and liaised with the TF/slab provider. 8. It's also worth bringing in your window supplier early on - we needed to form recesses in the concrete slab so that when the lift and slide doors went in we could get close to a level threshold.

Yes I have 100mm wood fibre board on the walls (rendered) and on the roof as the sarking board. Building control accepted it for the building warrant and the structural engineer had no issues. I am not sure if the wood fibre gives enough racking strength on it's own. Our SE specified an OSB layer on the inside of the roof frame, and 2 layers of OSB on the inside of the wall frames to give the building the required racking strength.

I found it helpful to lay off the drink for 24hrs...

Yeah they won’t issue it until you’ve got the completion certificate. My surveyor didn’t bother coming out again when I got mine. Make sure they don’t do a sneaky on you and backdate it. It should be dated from the completion date as they won’t issue it before then. This is a common trick it seems.

We had solar thermal on the house I knocked down. I'm afraid i didn't even bother reusing it as it was never that great and the cost of someone taking it down and putting it back again would have bought quite a few extra solar pv panels.

Ah well if you’ve got them anyway ... Best for DHW in summer however.

Very much better value to go for PV panels, as you can use the energy generated for pretty much any purpose, they cost far less to install (in terms of cost per kWp), have no maintenance requirements etc. We originally fitted a thermal store, but found that the heat losses from it made the services room far too hot (over 40 deg C) and cracked an oak door, as well as making the adjacent bedroom too hot in summer. I removed the thermal store and replaced it with an electrically heated Sunamp phase change thermal battery, that works like a combi boiler, and instantly heats hot water. It's not perfect, and Sunamp need to refine the control system, but it's massively more efficient than the thermal store. Today, for example, our in-roof PV array had fully charged the 9 kWh capacity Sunamp by around 11:00, and I could have used the excess PV generation for the next few hours to charge my car, if it wasn't already charged up.

I have solar thermal but as @Alex C says it’s not very useful in the winter when it is most needed. If I chose again I would have PV instead.

This wouldn't work as you won't get much out of the solar thermal in winter when you need the heat. Why use solar thermal when you could just use pv and divert excess to the thermal store. PV is far more flexible than solar thermal. I have had both in the past and would not bother with solar thermal again. What other heat source have you got going into the store? I hope you weren't just planning on using the log burner

Our house requires pretty much double the heat of JSHarris but is also about double the volume from memory. To keep the air temp at a constant 21.5 takes very little additional heat as most of it comes from cooking, appliances, showering etc but we we do tend to have 3no. 600w towel rails come on for an hour a day through the winter. This keeps the bathrooms nice and warm, dries the towels really quickly and also adds some heat into the building. We also have UFH pipes in the slab (ground floor only) just connected to the smallest gas boiler I could find which modulates down to 3kw. We don't actually need much heat in the slab to heat the house but it is much nicer walking on a 23 degree tiled floor than walking on it at 20 degrees. A small amount of heat input a couple of times a week is enough to just keep the chill off the tiles so we can walk around bare foot comfortably even in the middle of winter. We run the UFH pipes with no added heat input during the day so that any solar gain onto the slab is moved all around the ground floor rather than just making a warm strip next to the full height glazing. A log burner would create far too much of a temperature spike in a passive house, better to have a small heat output for a longer period of time.

I've just set one up using edging blocks tipped outwards and I'm going to have a trowled chamber and arris where this joins. Concrete will protrude out around 20mm past door but not to concerned about small amount of rain running onto it. Could paint/tank this strip. Gradient I'm doing an inch or so in around 1200mm with paving set half inch below kerb blocks

None of them will ever pay out Go for the cheapest Ours has only visisited us twice First time he didn’t get out of his car “To muddy” Second time he came to inspect the roof But didn’t go on the scaffolding But if we ever had to sell on the next ten years It May have limited our options Looking back I wouldn’t of bothered There’s plenty of companies that will do one retrospectively

The gradient is not the issue, it's the rate of change. I see lots of people have a very short very steep ramp which could be either the clutch burner, or spoiler catcher. Why not just grade the aproach so you make any necessary rise over the length of a car? We have the opposite problem, the garage is lower than the road so we have a slope down to the garage, then a very small step up (with a drainage channel) to prevent heavy rain filling the garage.

We just have UFH, with the pipes cast into the passive slab foundation, so only on the ground floor. Our absolutely worst case heating requirement, with everything in the house turned off except the heating and MVHR, no occupants, a set room temperature of 21 deg C and an outside air temperature of -10 deg C, is 1,600 W, though. In practice the house never really needs more than about 500 W at the most, though, as with a couple of hundred watts of incidental gain from appliances etc, another couple of hundred watts from occupants and an outside air temperature in winter that averages at around 4 to 6 deg C, the house doesn't really need much in the way of heating at all. We run the UFH from an ASHP, but that's not cost effective, as we will never recover the capital cost of the thing from the electricity it saves (we are all-electric, no mains gas here). If we wanted the best value heating system then that would be to fit a WIllis immersion heater inline with the UFH and pump, and just use the ground floor slab as a storage heater. Run from E7 it would only cost slightly more to run than the ASHP, and has the advantage that the capital cost would only be a couple of hundred pounds, rather than a couple of thousand for the ASHP (that difference would buy enough electricity for a decade or so of winter heating). We have no other heating, other than electric towel rails in the bathrooms that are automatically switched on and off in the morning and evening on a time switch controlled circuit (plus they have their own switches to disable them if they aren't in use). In theory we could heat the house using the Genvex MVHR, just as we use it for comfort cooling, but in practice neither of us like the slightly dry air that warm air heating tends to give. This is very much a personal preference thing though, as @PeterStarck uses his Genvex MVHR as their main form of heating and they are very happy with it. We had an open weekend a couple of years ago, where we we had around 60 people visit the house over two days, in groups of three or four, for an hour or so each. One couple had just completed a passive house build and had chosen to fit a tiny wood burning stove (a room sealed one, intended for use in canal boats I believe). I think this was one of the very lowest output units that was available, around 2 to 3 kW IIRC. They related their experience with it, when they lit it for the first time on the previous Christmas Day, when they had family around. Apparently the living room quickly warmed up to well over 30 deg C, and even with all the windows open it was too hot, so they evacuated the room, shut the door and left it with the windows open until the fire died down and the room cooled (which was the following day, apparently). When they visited our house they mentioned that they were in the process of getting the flue and air supply duct blocked off and having an LCD screen fitted behind the front of the stove to display a flame effect. If you want real flames and a low heat output, then a bioethanol stove or fire might be worth looking at. They don't give out much heat, don't normally need either a flue or an air supply (so good for airtightness) but they can be a bit expensive to run, if you use it a lot. As a feature, that's only used occasionally, I think they are probably a good compromise for those that really want to have the look of open flames in a room in a passive house.

You can pretty much heat our house by getting the kids to run around and the dog farting.

We are next to fields and I think they put so many chemicals on them there aren't many flies left. We just seem to have a week a year when tiny storm bugs get everywhere, oh and also the ladybird invasion before Christmas, definately no window opening then.

Fly screens! After 10 years in a house backing into a canal I heartily recommend fly screens. We retro fitted a year after our build was complete last time - this time we are planning then in from the start.

I take your point, but assume that you aren't plagued with cluster flies! This is the second house we've owned which has been a magnet for the damned things, and we've learned over the years that there isn't anything much you can do about them, other than not open windows and open and close outside doors as quickly as possible when going in or out during cluster fly swarm periods. From all I've read up on cluster flies over the years, I've not seen anything that's a reliable predictor as to whether or not a given house will attract them. Our neighbour on one side never has a problem with them, the neighbour the other side has much the same problem as we do. Once they decide they like a house they will keep coming back, pretty much no matter what you try to do to dissuade them. This leads me to believe that relying on having to open windows to get ventilation at the design stage may not be wise, as there is no way of telling at that point whether or not the house is going to be a "cluster fly magnet", other than, perhaps, if it's in the middle of a large town or city, where the damned things don't seem to be a problem.

The windows hardly every need opening. I am just talking about a basic principal of cross ventilation and night purging. The op's architect has incorporated this as well by having an automatically opening roof light. I understand there are other ways to help cool a house, but none quite so simple or fool proof.

But why have to open windows, letting in bugs, unfiltered air, etc, when the MVHR can just do it with no reduction in air quality or need for any form of intervention? We do have opening windows in every room, but never bother to open them. One reason is that we're in the countryside and plagued by cluster flies whenever the sun warms up the outside of the house, so the last thing I'd want to do is open a window and have a house full of flies within a few minutes. The cluster fly problem goes away by late spring, but then so does the overheating problem. Sadly the cluster flies come back in autumn, just when the house is prone to occasional overheating again.

I designed my own passive spec house to have at least 2 opening windows on different elevations in each room (but only 1 in my office as it has rooms on both sides) and also with 2 large roof lights at the top of the open plan landing that open automatically at 25 degrees c. This makes purging heat in any room really easy as opening a window in the overheated room moves the heat outside in just a few minutes. There aren't that many times a year that opening a window at night dosen't cool a house down. This is all pretty standard stuff and is something any architect should be looking at doing in a new build.

Just as @Bitpipe says, opening a window doesn't do anything much, and creating a cross-draft by opening windows at either end of the house works, but tends to make rooms that aren't too hot a bit cooler than needed. With the MVHR in active cooling mode (it switched to 100% bypass and passive cooling mode a couple of hours earlier, I think) it tends to preferentially cool the bedrooms, as i've set those up to have a fairly high flow rate. This is ideal for cooling, as cooling the first floor (which doesn't get much direct solar gain) tends to limit the amount of heat that rises from the large entrance hall space, as long as we keep the bedroom doors closed during the day. The other point is that I don't want to have to faff around opening or closing windows, so the house systems are set to regulate the environment without me needing to twiddle with anything. The cooling is set to come on when the upstairs landing reaches 24 deg C, and at first it will try to passively cool by just switching to 100% bypass and feeding cool air from outside into the house at a low flow rate (the normal background ventilation rate) and if the temperature continues to rise the MVHR will automatically increase the fan speed, then turn on the air-to-air heat pump.

I share the stove concerns. That lounge would overheat very quickly. We do have a stove and we do use it, but our kitchen / diner (similar size to your lounge) opens with double doors straight to the stairwell, then double doors the other side to the lounge. With all doors open it is pretty much the whole ground floor open, and a stairwell to let heat upstairs. Like this with everything open, the stove can be used carefully. But in your lounge, with little obvious route for it to heat the whole house, I think you would kust overheat that room very quickly indeed.

@jsharris couldn't you just open a window rather than having to run a cooling system? Our living room got pretty warm today as we have quite a bit of south facing glass as well. I generally don't mind this in the winter as the house is open plan the excess heat tends to disapate around the house and not be a problem. The heat absorbed into the slab today will keep the house warm for the next few days with no additional heating requirement at all.

As if on cue, today has provided a good illustration of the way a passive house can overheat during spring and autumn, or even winter. Today has been bright and clear, and despite the shading overhang over our south-facing glazing (which does nothing at all at this time of year), despite the fact that our heating hasn't come on at all for the past two days, and despite the fact that we have heat-reflecting film on the outside of our east and south-facing glazing, our house reached well over 24 deg C early this afternoon and the cooling system came on for a couple of hours. The outside air temperature didn't exceed 8 deg C all day, and was around 7 deg C when the cooling system came on. The house is now just under 23 deg C, still a bit warm, but we would have been in for an uncomfortable night if the cooling system hadn't come on for a couple of hours and cooled the bedrooms down to below 20 deg C. We have suffered from the house getting a bit too warm in the spring and autumn, when the sun is low in the sky and penetrates deeply into the house, bypassing the shading, but I can't remember the cooling system having to come on in January before. The saving grace was that our PV system was generating a fair bit of power all day, more than enough to run the air-to-air heat pump that is built in to our MVHR system and which provides comfort air cooling. So. to sum up, I think your design definitely needs some better shading on those large glazed areas that face south, if you are not to suffer the same sort of problems that we've had to deal with. I modelled our house in PHPP, and accepted a small overheating risk, without realising that any overheating risk shown in PHPP can be unacceptable, because of the very long thermal time constant of the house, which is a consequence of having a long decrement delay structure and low heat loss rate.

I'm hoping a couple of weeks skiing next week will revive my enthusiasm ??

I used Titebond Polyurethane Construction Adhesive. It's expensive but you don't have to worry about damp or cold.

I have a passive spec house and agree with all the points made above by others that do as well. Your architect may be qualified to design a passive house but if he dosn't actually live in one he may not fully appreciate things like the risk of overheating from sun and fires. There is no way you will ever use a log burner. Your south facing double height glazing will massively overheat the room. The brise soleil as drawn will do nothing except for a couple of weeks around the longest day when the sun is really high in the sky. A normal rule of thumb with brise soleil is to make them protrude from the build by half the height of the glass they are shading. Even this would have overheating issues in spring and autumn. You have quite a good roof overhang on the south side to shade bedroom windows in mid summer, this will be helped more if you recess the windows well back into the wall. Even so the bedrooms are likely to overheat without any external shading. External venetian blinds as used by others on this forum and also myself are not an expensive luxury but a necesity in a passive house with lots of glazing. I would also worry about your lounge cooking in the evening late summer sun Bed three and four will have a real issue as there is no cross ventilation in these rooms to purge at night . I assume windows on master and guest open on north and south elevation to provide cross ventilation? My experience is that night purging with a large roof light works really well in an open plan house, but useless if it isnt open plan or you shot your doors. I would also suggest getting rid of the sun tunnels. You have. passive spec house, then are making 14" holes in it with an uninsulated tube. Budget for some quality light fittings instead. I would suggest that for such a grand house the corridor on ground floor is way too narrow. I think it is also a massive mistake to make your dinner party guests leave the grand dining hall and squeeze past your muddy boots to take a pee. Generally I think it looks a really interesting build and I'm sure will be a lovely place to live.

why not make stud wall on the floor to start with make it short in height - use top packers -then apply glue to bottom rail when you raise it up and fix top rail with spacers if needed to make it tight . lot easier to make stud wall on its back on floor

893 a record? That's a typical post for some of the more wordy posters (myself included).

893 words. Phew!

This looks terrific @D Walter. Is this a self build or main contractor? All looks very professional. I like the blue bricks on the curved retaining wall. With the reinforced concrete walls and floors it will feel bomb proof! Did you look at doing a blog, as I had to switch between this topic and this one If you did this as a blog it keeps the thing together and the comments appear at the bottom of each blog entry.

sorry for the rant by the way........I'm not really angry, just Impassioned...

Get a data sheet for each quote. The range of 3G is massive. You can get 3G that's so poor a good 2G is better. When comparing make sure you compare the u-value for the window and not the glass. A lot of sales people give you the u-value of the glass only as it's a lot better than the full window (frame and glass) to make their product look better. If in doubt ask us to help compare them.

Lovely house aesthetically but +1 on the WBS & solar overheating. Was snowing this morning and as I ran the hoover round in my t-shirt I was already feeling warm in our Passive standard house. UFH (ground floor only) has barely come on this winter at all. You have a massive south facing window in the dining hall which will make it very uncomfortable year round unless you use external blinds or apply a reflective film to the glass. On our build, purely by virtue of the plot orientation, we minimised south and north glazing. After a few months in an overheating caravan in the garden we specd external motorised shutters on the east windows (wall and roof) - omitted one south window in kitchen and in spring and autumn when the sun is low, it really heats up. West glazing is not as susceptible but still makes an impact in summer- we have internal lightweight drapes that reduce the effect but will probably build a bris soleil to give us a bit more shade. If your architect has considered these elements then it would be a bit of an alarm bell as to whether they understand the implications of building a well insulated, airtight home (whether passive standard or not). Get it modelled in PHPP or equivalent.

It would be useful to have the calculated internal floor area. The design incorporates some wow features with its baronial dining hall space and dedicated gym. I hope the internal gym wall will be mainly glazed to connect it with the hall area. I feel the kitchen is undersized for a property of this stature and the lack of a walk-in utility room and preferably a pantry is a major miss for me. I have some specific observations on the sitting room having lived in a property with a similar size room and with the internal door in the same position. The double focused furniture arrangement does not work and actually caused interpersonal schisms. I would loose 3ft of glazing on the west wall to allow the stove to be centered further south on that west wall as this will promote a central furniture arrangement. Have you and your architect experimented with larger eve overhangs? What about wide plank timber cladding? Have you or your architect lived in North America, I ask because there seem to be some design choices inspired through living in another culture.

Very nice plans. I would be concerned with overheating and would want this modelled. The proposed overhang does not look like it will mitigate this. The lounge looks the most vulnerable. Hoping that is not a wood burning stove in the lounge as this is at odds with clean, modern living and if the house is properly insulated it would need to be minute to prevent overheating, even on a cold, cloudy day.

Mine is a portal frame and each individual part of the frame was made in the factory and fitted to the sole plate on site.

Start by fitting an accumulator, that will maintain the 2 bar pressure until you have emptied the accumulator. A pump would need a break tank and gets messy. you can't just suck water out of the mains pipe with a pump.

Interesting. Looks very well thought through. First, compliments on the use of colour - makes the plan much easier to understand. Only one comment about the plan; consider changing the southern dressing room to a mezzanine ..... ?

I've never seen the learning behaviour, but according to the manual it must have done it when I originally wired it up for the very first time. It doesn't do this every time it's powered up, though, as it seems to have a supercapacitor inside to allow the calibration to be remembered for a fair time. There is a procedure for getting it to recalibrate, which involves powering it on for 20 seconds, then powering it off again within one minute, then powering it on again, when it will go into the calibration mode. Mine's powered off except when there's a call for heat, and it opens up and starts to regulate within about 30 seconds at the most, until it has settled to its initial opening point. I've not seen the 2 minute turn on time that is given in the manual, and suspect that may be for the worst case condition As the manifold starts to heat up it will occasionally motor the valve for a few seconds as it readjusts, but that's all. When powered off the internal spring just winds the valve back to being closed again. Mine is screwed tight down on to the head, and isn't at all loose. The manual for them is here: https://www.salus-controls.eu/media/product/docs/thb23030-qb-we-v003-compressed.pdf

My brief view. A competent AT should do a good job. A competent architect should add a measure of inspiration. A client using an AT probably needs to supply that inspiration A client using an architect needs to direct and ground the Architect's inspiration. As Peter says, you pays your money and... hopefully after taking the time to learn your role in the dance with whoever you choose, and to have learnt to choose the right partner in the first place. A lot of spadework first makes for a better tree later! F