Stones

We are all on one level so don't have this issue, other than our master bedroom. tends to sit 0.5C below the set house temperature, whilst the rest of the house sits 0.5C above it. The room is heated in exactly the same way as the rest of the house. The only difference is that the MVHR supply rate to the room is (intentionally) set higher than other rooms. In previous houses, where we have not heated rooms, temperature in those spaces was dictated entirely be the temperature of incoming MVHR supply air. For those with this issue, a strategically positioned inline duct heater may be worth considering to lift the temperature in the relevant areas?

I've got our master controller/thermostat set to 21C. Most of the house sits at 21.5C, our bedroom slightly less, due I think to the increased level of ventilation to that room.

@Ricco Have a look at the company linked to in this thread: Notionally trade only but were happy to supply to me as a self builder.

@Declan52 Based on a kWh electricity unit price (inc standing charge) of 12.3p, I paid 3.32p per kWh of delivered heat, and 5.34p per kWh of DHW (inc losses). Just under £300 for DHW and just over £200 for heating last year (includes amortized cost of standing charge). Been a bit colder / higher wind speed recently so looking like this year will use a little more energy on heating.

@joe90 Heats to 50C for DHW Flow temp varies (weather compensation) on heating side but I've not seen it more than 33C in winter, albeit generally under 30C.

As many of you know we opted for a pre-plumbed ASHP and cylinder package that came with a master controller. As I've reported in my blog, it works really, really well, the only input from me being the target house temperature. The control system works on a weather compensation basis but 'actively learns' what the house requires in terms of heat input. Internal temperature is very, very stable, (house generally sits 0.5C over set temperature) and only spikes if we have prolonged periods of solar gain. This is the second house we have lived in where there is an even temperature 24/7. Wouldn't revert back.

@gc100 Welcome to the forum. It's certainly one strategy, although bear in mind, architects and QS's can make mistakes (+/-) as well. I've built six houses, and for 5 of them, tendered using build reg drawings. For our most recent house, I used the planning drawings to tender. With each set of plans I provided a detailed list of specifications covering everything I could think of, from shelves in wardrobes, to specification of slabs to be laid. No reason why you couldn't do the same yourself?

@Ballynoes I now live up in Orkney, where winter temps average in the 0 - 4C range (rarely colder) and there is high RH due to coastal position. I run an ASHP without issue - over the 12 months March 2017 – March 2018, heating COP ranged between a February low of 3.3 to an October high of 4.6 over the course of the heating season, with an overall SPF of 3.7 DHW COP ranged between a February low of 2 to a summer high of 2.5, with an overall SPF of 2.3 Colder and drier air temperature is in many ways better for an ASHP compared to the 0-4C range. If fitting to a new build and appropriate heat emitters and hot water storage, ASHP can work very well. If you want to speak to someone local(ish) you could try contacting Home Energy Scotland - they hold details of installations which you can visit and get real world feedback from owners (rather than sales pitch). Out of interest, how close to Dunkeld are you?

+1 @Russell griffiths ?

There are many ways to skin this particular cat. I did a cost comparison of ASHP vs direct electric vs oil vs LPG, all with and without solar PV. I spent a lot of time looking into Sunamp (PVs) as they were then, and had long conversations with them persuading them to consider the concept of extension boxes to increase capacity, but in the end, for our house, and what we needed, an ASHP and UVC was easier, cheaper to buy and cheaper to run, even after accepting the lower COP / higher cost of providing DHW using an ASHP. The cost per kWh of DHW (inc all losses) delivered to the tap is significantly less than I would pay per kWh for E7 electric. Heating is cheap as chips. I bought a Mitsubishi Ecodan and a 300L preplumb cylinder. UFH is fed directly from the ASHP (no buffer - no need!) and we have not had any issues with running out of DHW, despite the sometimes heavy consumption. Previous cost comparisons that I have done indicate that when your heating requirement is 2500 kWh or less, and DHW requirement 2500 kWh or less, then direct electric is the cheapest and easiest solution. After that other technologies come into contention and it is a case of trading off positives and negatives of each. For GSHP, although they have better COP than ASHPs, they can have higher running costs when heating demand is low (5000 kWh or less) due to the increased costs of running circulation pumps and replacing antifreeze. I've detailed everything in my blog if you want to read more.

Heated to a max of 50C, cylinder normally sits at 48 / 49 C when fully charged.

As part of the process in selecting our preferred DHW / Heating solution, I considered heating DHW to a set temp using the ASHP then topping up with immersion to get the desired target temperature, but on costing it out, found that any savings accrued on the ASHP side in terms of improved CoP were offset by the cost of running the immersion. In simple terms, (without PV) it cost the same either way. Why complicate things when you don't have to?

Welcome from the far north.

@Declan52 Do you suffer noise from the shutter flaps clattering in stormy weather? I would have preferred vented direct to outside, but experience in the houses we rented up here during the build was that such devices were defeated by the strength of the wind gusting.

+1. My understanding was the original PH standard was set at the level it is, because it was possible to provide such limited heating via an electrical heater in the MVHR, i.e. no requirement for a full CH system. It does not mean no heating is required. As referenced, there are many factors which will impact on your heating requirement. We live in an exposed position where wind, rather than low temperature is the main heat loss driver. In addition, our house is 'n' shaped, increasing the surface wall area exposed to the elements which drive that heat loss. One of my colleagues built a house using the same ICF system as us, but opted to forgo UFH, relying instead on a post heater in the MVHR and 4 oil filled radiators spread between key rooms. The temperature differential room to room is quite noticeable. He has been honest enough to say that he regrets not fitting UFH, if for no other reason than comfort.

2.4 metres

I've seen open spaced timber cladding fitted over a simple membrane and recently over profile metal sheets. I would have thought roof overhang and how exposed the site is in terms of weather would dictate type of backing.

I was reading an article earlier today suggesting the oil price could rise to $400+ a barrel if sanctions are imposed on Saudi Arabia and they choose to retaliate. Not convinced by that, but you could imagine a scenario where they choke off a % of supply to shock the price up.

@recoveringacademic - looks like you need it! Well done though, pat on the back for you both.

I've been looking into this recently. The definition (sizes) are specified in the 1960 Act, amended in England but not Scotland. Various stated cases have clarified some of the finer points. Basically, can be built on site and does not have to be moved by road (but must have the capability to be, although not necessarily access to). The main advantage seems to be you would only need a building warrant for the foul drainage. Everything else would be exempt. If built so not within the definition, warrant required, the main issues being the various activity space requirements.

Regardless of the pump set up / capability I would try and avoid putting anything down the toilet that is not human waste or toilet paper. Sanitary products, baby wipes, contraceptives etc do not break down and will not do your treatment plant any good at all.

Treatment Plant install will be similar, i.e. set plant to correct invert level. Whether the outflow level matchs the burn is another matter, worst case you might have to discharge into a chamber and a float switch pump will shift the treated effluent into the burn.

Of the many sites I've been to, this is invariably what is done - landscape / grade so there is no drop off the edge. The only instances I've seen where lips have been put in place are commercial applications or longer ramps which also had hand rails.

We went with a lightly textured multipanel, finding one that complemented our choice of tiles. Very impressed with it, a breeze to keep clean. 18 months on, looks as good as the day it was fitted. I'll post a picture tomorrow.

I wanted the slide and hide door, but didn't like the cheap toggle button control, and didn't think the touchscreen version worth the extra £££. Went for a Seimens self cleaning oven with sliding / pull out shelf rails instead.