MikeSharp01

Yep trick is to source as much in UK as possible and that's not easy. I think I have found the timber frame components here the cladding and about 50% of the insulation. Was warned by insulation supplier that price rise of PU is coming in January. Other Big ticket items however are very difficult like passive house windows. They all seem to be EU based as are the MVHR units. Still we are keeping the local professionals busy Architect / SE and Jewson. Must get timber ordered.

Ok so two flow meters one in the waste water and one in the heat exchanger, four temp probes one in each input and output and a data logger! Then a bit of integration should lead you to how much you are getting back. The question is from / via where is it coming back! Easier to use a pair of range assumptions. Assume 10% efficiency (worst case) so for every hundred litres of hot water you get back 10L and 64% as quoted in the Recoup literature (which is IMO more than you can expect and perhaps therefore a bit missleading) and get back 64L I think not!!!! The answer will be in that range somewhere, probably nearer the the middle than the top. You could look at it another way. 1. You only shower in hot water so you don't really care about the inflight cold water at the start of your shower but you need to know how long it runs cold for, call it ifh. 2. You shower for 4 minutes and use 40L (10L/min) @ 40degC @Nickfromwales would approve. 3. Plus (and this is where the time derived form 1 above is important) you have left ifh seconds of hot water inflight to the shower head and it is now cooling down and it won't go through the Recoup device. Lets say ifh is 15sec (I would hope a lot less!) you have actually used 42L of water @ 40 degC. 4. So you loose almost 7% that you cannot recover, so even if perfect only 93% is available to recover. 5. Some heat will be lost as the water cools, flowing over you - a somewhat cool 37 degC, the shower tray, down the plughole and along the pipes to the Recoupe device. Lets say it drops by 5 degrees. (You could measure this with an IR device at the top of the recoupe device I guess) 6. So once the HW hits the Recoupe its down to 35 degC so its given up another 17.25% (assuming your incoming CW is at 6 degrees) of its heat 7. You now have just 40L of water at 35 degC now only carrying 76% of the heat you lovingly put in at the generator end. 8. Now multiply that 76% by the 64% efficient (assuming system A and the recoupe figures) and you get 49,25% 9. I think that means you might get back about 49% of the usable shower from the Recoupe device itself! BUT because you have a neat little MVHR most of the heat coming from the inflight hot water now standing in the pipe, the heat given off by the shower tray and pipes as they cool and that generated by your good self giving yourself a good rub down with a towel (you may of course be lucky enough to have somebody else doing the rubbing down in which case you can double the output) will be kept in the house anyway so in a very real sense you get much of that back also. Not unreasonable to expect the MVHR to be 90% efficient. Extending this idea a little further we find that its not so much how much you get back but rather only how much actually goes to waste having run through the Recoupe device. It looks like a good proportion of rest is kept about the place via the MVHR. Hmmmm... I think I will go and have a snooze after that and contemplate not bothering with traditional waste water heat recovery but just slow the output flow down enough to let the MVHR pick up heat from the pipes as they cool... and just let it go in the summer!

1. Cos they could not predict the future - of insulation. 2. The client didn't want to pay for copper they didn't need although the cable supplier would be very happy. 3. They worked out that across all their jobs the resulting voltage drop would be wasteful, requiring more power stations then heretofore even if it made little difference in this one job. (Green before their time so perhaps they could have predicted the future!) 4. Nailing cables onto sky hooks not taught on their ONC / NVQ. 5. The boss worked out that across his lifetime the resulting increase in costs associated with the cable clips would mean he / she would not be able to: get new car / retire early / take up with a toy boy / girl - dump the wife / husband and still have something in the bank.... I could go on - perhaps somebody will. HOWEVER this does not mean I don't feel your pain - empathy is everything you know.

What system are you using for this, should be possible to get an idea shouldn't it, amount of water x temp delta x efficiency of the system or have I missed something, only looked at such systems in the first stage, have kept the waste water separate from the 'number 1s & 2s' to the plant room in case it looks like a worthwhile proposition. (Must add that to my post above about things to remember.)

Yes that is what I meant but its only mixing down with the return flow from the UFH and the other high grade losses will only be in the pipework between the heat source and the UFH mixer valve. However your point about high grade heat, what is your definition of high grade I wonder, and mixing is a good one and perhaps we (I) need to think about it in energy terms more directly. My thinking was that the boiler would only deliver what was required, modulate down and stay within its efficiency range, once the hot tank was filled. Trouble is, when you expect that, the efficient modulation range of the boiler (or other heat source) I think the smallest boiler goes down to about 3Kw which I suspect is much more than you would need to put into an already warm slab which is surrounded by an airtight and well insulated structure. Your other point about getting the floor temp down is a very good one that needs thinking about, as you say I also seem to recall JSH struggling with that one as well but I have not followed it up. Is the limit set by the mixer valve I wonder. Off I go to read the JSH stuff again.

This is possible because the UFH will (can) mix return water from the UFH with hot water from boiler to control slab temperature the full hot water can go off round the hot water tank.

Yes Jack you can get by with 55 deg in the UVC but how many showers can you have and you still have the standing losses? Not sure but I get the impression that showers are at the core of all the DHW challenges.

Should not this problem be kicked back, along with costs, to your architect as they should design to part M. In a job I worked on, albeit for a public building, they made us zig-zag the ramp across the steps up to the building to keep to the 1:20 so I guess you might need to work out a a 1:20 plan, as I mentioned elsewhere here today this is not about you today but about those who come after you and might need access.

We included the shed because we were worried, and we said so in the submission, and in the end they said nothing about removing permitted development rights in the planning permission when it came through.

Have to somewhat agree Peter but they can get caught out if it goes to appeal because the inspector will look to check the boundaries of their thinking in my experience anyway. Worked through 3 or 4 appeals (although with others) and this seems universally the case. The most common thing that helps is 'have they allowed similar things in the past' so if you can show that they have then they are likely to roll over. This is kind of built into their approach, an old friend is a retired planning officer, so red lines are really red lines cos once they let it through somewhere it will go everywhere unless they can block it with a change to the local plan (takes years). So just find examples of where what you want is already happening, ensure your argument draws on this, preferably many examples, and is set a little bit back from it, so you are not pushing the envelope, and things should be OK.

Yes getting some advice might help - essentially planners just apply the rules, local planning and national guidelines if you steer a path between them all will be well. The planners don't have a view on 'what they want' its just what fits within the rules. Interestingly our planners in Whitstable told us that they liked our application 'because it was different' and although it challenged the street vernacular it did not breach any of their rules. We did a preplanning check with them, cost £400 but was worth every penny because we had them on site and explained what we were doing and their only concern was the ridge height, as long as we stayed below a notional line they would be happy. In the end we went about 300mm above the line but by carefully arranging the massing of the building they accepted it because your eye was not upset when drawing a line between the ridges on each side. They even allowed us to have jet black cladding when they had made the next door house lighten their dark grey cladding. Our architect, not saying you cannot do it yourself, just took the local planning and national guideline rules and our spec and steered a path. Where it came close to being a risk they, with our help, beefed up the argument to show how we met the rules.

Yes, can you see all the way up it? If you can then its likely you have a negative pressure problem which the heat from the log cannot overcome, sometimes happens in 'funny weather' - try a smoke test if you cannot see up it.

Yes everybody says mains gas but I have a worry that its not a sustainable source of energy, but then what is? Although you can pack one hell of a punch with a gas boiler most people on here build homes that are so well insulated & air tight that the energy requirement for heating is very low to non existent, Domestic Hot Water (DHW) is the main challenge. There is loads here on that challenge (just use DHW in the search box to find out just how much). Last week I was looking at our system and although I had sort of concluded that a combi boiler that could deliver 2 x 10l/min showers was the way to go after @Nickfromwalespointed me at a unit capable of doing it. I am wondering if that might be overkill but it does have the capacity for showers albeit at a cost £ and some small standing losses in the internal preheat system. Although the final system will be an exercise in optimising the compromises you can, in the end, decide much of the detail down the line provided, it seems to me, that you get the basic infrastructure right and make some decision up front. There are also some basic myths to dispel. They are (and I am not sure it helps to understand them): Just because you don't have children and are happy to live the life of a hermit / hippy (nothing against them some of my best friends still are) the people who will purchase your home from you or your estate will pay more for stuff they understand (get). The price of energy is low. True it is now but won't always be. Being self sufficient in energy is a good thing. Not necessarily true because you have to live with your neighbours and they with you so unless you can find a self sufficient solution that relies on no technology you will have to rely on somebody just to keep making the service parts etc. This leads to some upfront decisions - these appear to be: Want to be a) net exporter of energy (SAP > 100), b) use no external energy, sum of external input - generated output = 0 (SAP = 100), c) use some external energy (SAP <100) If you go for options a) then you will inevitably need some sort of energy storage system to smooth out the generation curves you are likely to get unless you have access to something like Hydro generation and even then... We have : Natural Gas, E7 or E10 but will need to change supplier, Sun - so could have PV or ST We don't have: Provision for wind (not enough space), Hydro - no flowing water to speak of, We won't have: GSHP -small area available but costs very high, Oil & LPG So far on my list of 'infrastructure' I have: Ducts to get ASHP services into the the building and to the plant room (at this stage I don't intend to install an ASHP) but given the cost of small piece of ducting.... Ducts to get additional PV, for garden mounted PV cells, into the building and to the plant room. Ducts, or just routes, to get Roof mounted PV services to the plant room. Enough room, and wall pattressing (extra strength in the walls), in the plant room for the; MVHR, a Thermal Store (TS) or UnVented Cylinder (UVC) or a phase transfer storage system, a boiler, a couple of heat exchangers, 3 - 4 pumps and associated valves, pipework & wiring. Space somewhere for the control panel (in our case not in the plant room but in the downstairs WC where one wall is spare! - there are reasons.) UFH - which we technically don't need, Passive House Planning Package (PHPP) says warm air will be enough, but it unlocks a whole mass of possibilities for heating, cooling and moving heat about. See the @JSHarris blogs for more on that. I will not terminate the UFH other than to pressurise it for testing and during the slab pour. I think the cost of installing it will be around £400 but I, or my descendants, will get this back from the people who buy it safe in the knowledge that it has UFH available - not many people understand hot air although a lot of people generate it. Provision for in duct cooling and heating around (or in if you can afford one with it built in again see @JSHarris) the MVHR box. Can be fed from boiler, or ASHP if installed or could be electric heating (cooling not simple with electricity alone) Masses of insulation around the plant room to help with any standing losses, effectively isolating it from the house so what happens in the plant room stays in the plant room. I would like to eliminate standing losses if I can, I am sure I read somewhere here that @SteamyTea got to a point where his DHW energy use was the same as the standing losses so 50% of energy is notionally going to waste but probably heats the house in winter but is a problem in the summer. Using the MVHR to extract warm air from the plant room and redistributing it make sense but the cost of generating it in the first place needs to be considered - IMO I have also provisioned for a battery store adjacent to the garden room and can use the existing electric ducting to carry the connections back to the house and generation points. Have kept waste water separate from the raw sewage down to the plant room in case I feel the need to deploy waste water heat recovery via a simple heat exchanger. (Added 21/11/2016 when reminded) Some things imply other things so: if you go for ST then you probably will need at Thermal Store and a UVC won't work. If you have ASHP you will need supplementary systems to make DHW and you will probably need Underfloor heating and a buffer tank to optimise the ASHP output. It is unlikely that you will install both a TS and a UVC In short its probably one of the most difficult choices out there if you have a conscience and want to do the best thing for your finances and the planet. Hope this helps - could write a book by combining the people on here but I am not sure you would arrive at a consensus unless its to agree that there is no one right answer.

Just watched it, Ali - they spoke about it on the show and I froze frame on window and it looks triple glazed.

Somebody has to be - great up there.

There are companies all over I guess but your SE will tell you what they need and you pass this to the soils company. In our case we just told the soil testing company that the SE wanted a survey and they knew exactly what was needed. They chose the sample points and the depth to go. In our case 6m down in two places. Cost was £970 + VAT and he came from spalding to east kent so might come to you. Message me for his details he may know someone up there if not able to do it himself.

Nick, if you are still out there, is that boiler classed as a 'storage combi boiler' I wonder. Looks like only the efficiency is taken into account and heat losses from storage combi but still reading (page 24 of 234)!

Not sure just looking through the manual on the trail SAP software I have (From Energy Design Tools) to see what effect it has. I guess its like all of life, its about optimising the compromises!

That would solve part of the problem, the local water supply is excellent I measured it at over 50L minute on a 25mm pipe, I am still thinking that I will put a SUNAMPPV in line with it so I can get the PV excess stored but not clear how we control the two working together although the sunamp does say it works with combi boilers. I guess you just wind the output temp down from the boiler and recover it from the sunamp but as the sun amp wilts I guess you need the combi to work harder or can you line them up the other way around and deliver the output from the sunamp at the input to the combi? PS does the size of the boiler affect the SAP calculation, must check that!

Actually it might not be a Combi as I am struggling to get a one that can deal with 2 showers at once so might have to go back to a thermal store and a tiny boiler for just the air battery, the three towel rails and one radiator.

Has merits but the run is so long that even with very small bore pipework it will take a long time to get HW to the bathrooms / kitchen and the flow won't OK for 2 showers so have to stick with boiler in the house somewhere.

Am trying to source a length of gas pipe to carry the gas supply from the meter, in its box in the utilities building, under the garden and into the house. I understand I cannot use the plastic pipe as its beyond the meter but I am wondering what the alternatives are to this pipe system as it works out rather costly for a 25m run although I can get away with the smallest ID pipe as I am running the smallest boiler there is (11Kw I think) for DHW only! Any thoughts or ideas?

Do you mean model railway?

Magnetic base rotabroach, a decent sized cutter - 50mm (65mm is biggest most of them will do), some oil and word with your SE about where best to have holes will sort it in no time, save hours of running round and meters of pipe and cable.

How was this resolved, Terry, in the end or is it still ongoing?