Stones

Our main room is 4.8 m high, 5 metres wide and 9 metres long. It doesn't feel or look strange at all.

I've seen this done locally. They used profile metal sheets to provide the actual roof covering to keep water out, cross battened (which also secured the profile sheets and finished with timber to match the wall cladding - thin strips of timber with gap in between.

Why should you pay for defective workmanship? One letter sent to the original contractor recorded delivery, cc by email, giving him 7 days to put it right. If you don't hear from him, or he argues, move on, call the LA roads guy out to inspect (I think you should be doing this regardless if the workmanship is so poor), arrange your new contractor and get it done right. If the original company ever come back looking for money, you have a chain of proof of the defective work and your actions, you can deduct the cost of sorting it out and only pay them the difference.

I'd be wary of simply refusing to pay, and getting someone else in. I think you have to offer them the opportunity to rectify. I'd be inclined to say you've inspected the work, list all the problems, give them 7 days before you get the LA roads guy out to inspect the standard of their 'approved work'. If they refuse / fail to rectify to the right standard, that's when you revert to another contractor to sort it out.

I was chatting to my builder about this recently and for a project he is currently working on, has used a 360 excavator fitted with a crushing bucket to deal with concrete and stone that was dug up. He said it worked out under £4 per ton to get it crushed down and ready for reuse round the site. No disposal costs and no haulage costs for bringing new aggregate in.

We opted for a packaged ASHP and pre-plumbed cylinder. I let the ASHP heat all our DHW (to 50C), stored in a 300 litre cylinder. Over the 9 months that it has been operating, we have returned a CoP of 2.4 for DHW and just under (sometimes over) 4 for heating. I initially considered preheating DHW using the ASHP and topping up via immersion, but after working it out, concluded there wasn't any financial saving doing so - what you save on ASHP running costs, you spend on direct electric. Living in a coastal climate, we experience our fair share of damp and wet conditions. Our ASHP does occasionally go into defrost if it's trying to recharge the whole cylinder, but doesn't seem to have to when only recharging a partial draw off (say after a single shower). Our pattern of use is such that there is generally a fair gap between DHW being drawn off. I also let our DHW recharge according to a set DHW thermistor temperature drop of 9C rather than a timed early morning / evening schedule. Using an ASHP can work.

Quite clever actually, they buy a property for below market value, so get a far better return on their money in terms of rental income. They sell the property several years down the line by which time it has appreciated in value sufficiently (or so they hope) to pay off the remaining capital chunk to you and leave them with a tidy profit, as I'm guessing a share in any uplift in value is not included. Either that or the uplift in value allows them to borrow more against the property (enough to pay you off) and maintain their yield through continuing to rent it out.

You say he has full approval from the council, for what exactly? You say he has been renting it out, as what - holiday let (subject to business rates) or as a dwelling (council tax payable) or both? It sounds like the council tax chap has informed planning of a new dwelling, they have checked their records, and found no valid PP (hence my question about what exactly he has full approval for). 10 years would be the relevant length of time before the development was immune from enforcement (but still not authorised by PP). Paying council tax on it is not going to resolve the planning issue. More info required...

Sizing the chunks is down to however the adaptive system in the ASHP controller works. I'll be honest and say I've not looked into how the controller makes such decisions / what algorithims it uses. All I can say is that it works. I haven't measured the temperatures of each individual zone / loop. I have set the pump to over-run after heat input has ceased for 30 minutes and this does seem to keep all parts of the house at the set temperature. Again, all I can say is that it appears to be working for us. The next couple of months will confirm this and dictate whether I need to make any changes.

Both, I think, although to what extent I'm not sure. We have a mix of insulation types, not the best in terms of decrement delay, but certainly not the poorest. What I can say is the house seems to hold heat very well. Yes, this is exactly what we have done, both intake and exhaust roof vents on the leeward side of sheltered alley. Generally this does mean the ventilation is pretty smooth, although there are exceptions when wind direction changes, and wind speeds are high. I can't really add anything to your explanation of such heat loss other than to say given the climatic conditions, wet windy weather, we are going to see a higher level of heat loss compared with your own house. The point about airtightness is interesting, as I think we do experience ventilation loss when wind speeds are at gale force (40mph+), as you can hear what is normally a steady fan speed of the MVHR, being thrown out in high gusting wind. Our control system seems to be performing in a comparable way, despite the fact that the master controller hysteresis uses 1C increments.

Good buy, well done! How many hours do you think you have spent searching online before finding? - just interested in the effective hourly rate of your searching time based on saving (£400 - £600) made.

Agreed. We don't have a buffer tank, the ASHP just heats the slab directly in medium chunks (2 or 3 a day in cold / windy weather) We don't circulate the UFH constantly as others have / plan, it just doesn't seem to be required. Whist my system does have a back up heaters for both DHW and heating which would cover ASHP outdoor unit failure, it's not quite the same as a secondary fail safe Willis Heater which would in retrospect, been a very sensible idea.

Very interesting @TerryE. Fantastic results and I'm sure very satisfying knowing that your house seems likely to perform better than expected. It's a very good point that you make about keeping things simple, there is an elegance to using a Willis heater which is simple and cheap to maintain/replace. The downside of course is the higher running costs of direct electric. I would have loved to adopt the same elegant approach, but having sat down and worked out the combined capital, maintenance and running costs, I found that such an approach was going to cost us far more than the ASHP route we eventually went. For us, the tipping point was 2500 kWh/yr in heating requirement. Up to that level, your approach would have been the one we adopted. Unfortunately, our heating requirement (due in part to our house design with its large external surface area, and our exposed location) does exceed that tipping point by some margin. It's still very low compared to the vast bulk of the UK housing stock, just not low enough for such an approach.

Average wind speeds can be modeled and this is the approach I took when I was working out my heating requirement. The difficulty, as I have found, is modeling the impact of the increased pressure differential driving heat loss that comes with very high / gale force wind speed, which we have more than our fair share of. I'm 3 months off having a 12 month data set to be able to better quantify the impact such wind speed has, based on how the house has actually performed. Modeling wind infiltration discussed here: http://www.ebuild.co.uk/topic/16438-modelling-wind-infiltration/

Absolutely! The higher average wind speeds that we experience, plus the multiplying effect on pressure differential caused when we get gale force winds, really does have an impact on our heating requirement when compared to the requirement (modeled) if our house was in a sheltered location. We do however live in a relatively mild location, and the range of ambient temperature change is a lot lower than other parts of the country. We use a packaged system, with the master ASHP controller set in an 'adaptive' mode, which according to the blurb, learns how to heat your house. I think in effect, all it does is work out the optimum weather compensation curve rather than having to manually set it. I've yet to see the flow temp exceed 27C. I let the heating run 24/7 as a single zone for simplicity with the master controller thermostat set to 20C. Excluding solar gain (which we haven't had much of in the last week) internal temperature remains constant (+/- 0.2C) at 20.6C When we do get solar gain, the living section of the house can increase in temperature, but this is something that we are happy with (very similar in many ways to having a fire on). The heating clicks in, as and when required, with a 30 minute UFH pump over-run of 30 minutes. No other input from me and works really well.

Have you done a percolation test? How deep does the clay go? Could be you can get through the clay layer to something that drains.

As you know, the forum has two anemometers (donated by myself and @JSHarris) which it loans out. It may be in time that we expand the range of job specific tools / equipment that we loan out. It's something that the Forum Management Group will be discussing shortly.

You could always blog here on BH!

18 months ago we were quoted at £17.56 sq/m for the roofing sheets (but only after a lot of pressure to reduce the price given the additional on costs we had for haulage and a nod to the fact there were no local installers). Another £1800 for the ancillary bits and bobs, plus another £650 delivery costs from their depot to Aberdeen (they will not let you collect). We would have had a few hundred extra to get the roofing from Aberdeen to Orkney on top of that. Labour was estimated at £2703 Roof size circa 150 m2 Tata roofing costs £35.54 sq/m Labour estimate £18 sq/m Total £53.54 sq/m

Like @Russell griffiths we had self leveling compound on a garage floor. Seemed very robust, and I cannot recall it getting damaged. I didn't do anything to it, although probably should have painted it.

I think the biggest challenge is finding someone who you feel comfortable working with. I investigated working with an architect on a project we considered, and interviewed several. I didn't find it an especially enjoyable process, as none of the architects I spoke to seemed to be on the same wavelength or that receptive to what I wanted, one being more interested in somehow shoehorning in his signature design quirks, one not accepting that I couldn't build where he thought the house should go (land outwith the defined building plot) and one whose only interest was getting me to sign multiple contracts for a % of the build cost for several different professionals. I subsequently found someone I think I could have worked with but that was long after we had moved on to something else. One of the architects asked why I wasn't willing to engage him. The best answer I could give was like my place of employment, I could work with him if needed, politely and professionally, but wouldn't choose to do so if given the option.

+1 for a topographical survey. Very useful thing to have for planning purposes, setting out and further down the line when considering landscaping.

+1 @Moira Niedzwiecka I've built 6 houses now, and each has had its own challenges. Hold your ground and keep doing what you're doing and you will come through this stronger and with an immense feeling of satisfaction of what you have achieved.

Well done. Would be really interested to hear more about how you achieved the build cost you have, and the time commitment you put in (accepting a large part of the build cost saving was your own labour) over the course of the 1 year, 1 month. Do you owe friends etc who may have helped with various tasks an equivalent amount of time back for example?

I really do like the elegance of simplicity of being able to use a Willis heater to provide all the heat input into a house. I talked about such an approach with my plumber when planning our build and I recall him referencing one of his customers who used an electric towel rail element to perform the same function. Sadly for us, our heating requirement exceeds the circa 2500 kWh tipping point where direct electric was the most cost effective option.