Leaderboard

Perfect Straight onto the ICF with the first coat No mesh needed 48 hours then top coat with a spade of lime in the mix Gives a white wash look

I am currently investigating the use of an ASHP for our new house and came across this information following a visit from one ashp installer suggesting that 10mm plastic pipe to all radiators using a centrally located manifold was the best approach. This is from John Cantor’s website and he has written a book for those on the ASHP journey. I have just made a purchase - https://heatpumps.co.uk/ I hope you find this useful information... Potential perils of plastic pipe A college tutor recently suggested to me that the current environment in the heating industry does not encourage analytical thinking. Maybe I should therefore be less amazed when I come across plumbers who think copper and plastic pipe are interchangeable. Before you think I am anti-plastic pipe… I am not. The right size plastic is absolutely fine. Environmental considerations of the materal aside, a more direct issue is that of flow rate and pressure drops. Bore size of plastic is considerably smaller than copper, and it seems that this is often overlooked. If installers select plastic pipe instead of copper without checking the size correctly, this could have a negative effect on heat pump’s performance. (If you drop-off to sleep ½ way through this – read the scenario at the end ) With respect to the materials of plastic and copper, it would appear that the total energy involved in mining and manufacturing copper is far greater than the total energy (including the crude oil to make the plastic) to manufacture plastic pipe. Here is one site that discusses the topic , though not necessarily without bias. Another factor to consider, that mainly affects pipe runs to hot taps etc, is the heat capacity of the pipe material. Plastic has a relatively high specific heat, and the wall is thicker, but it’s light. The net thermal capacity of the two is fairly similar. (The cold feel of copper is more to do with conductivity from the hand than heat capacity) However, obvious factors aside, one of the biggest issues that could affect installations involving heat pumps relates to the internal bore diameter. This could have a very noticeable effect on the energy-efficiency of the system. All metric pipes are measured by their outside diameter. As can be seen, with common pipe sizes (outside diameters), equivalent plastic pipes have considerably smaller internal area to copper. This has a dramatic effect on flow characteristics. The graphs below illustrate examples of the relative internal dimensions of common pipes. (see AECB Water Standard) A brief note about smoothness – It seems a common belief that plastic is ‘smoother’ than copper, but the inner wall ‘smoothess’ of the two is about the same. However, plastic can be one-piece with slow sweep bends. In a different sense of the word, this is certainly ‘smoother’ than copper with tight elbows. Re inner surface, we can assume the two materials are about the same. Whilst it is fairly easy to look-up the pressure drop resulting from a specific flow rate with a specific pipe, we can see from the 2nd graph at-a-glance the relative flow capacity since the cross sectional area loosely indicates flow capacity. If a certain flow rate is required, then we can look-up the required pressure that is required across the pipe length (beginning of pipe to end of pipe length). The internal bore must be chosen such that the circulation pump is not overly large and energy-wasteful. This graph shows the approximate pressure required to maintain a certain flow rate for one specific fixed length of pipe example. As can be seen, the pressure drop along the example pipe varies very dramatically, so the wall thickness makes very big difference. In this example, we can see that a 15mm copper pipe could be used with a common central heating pump (shown at 3.6m head, 36kPa). However, if plastic were chosen, then one would need almost 9m head to achieve the required flow – far beyond the capability of normal circulators. On the other hand, if 22mm plastic were chosen, the pressure requirements would be only 1m head (10kPa) which is likely to achieve very low circulation pump energy. In real life, we tend to have a pump connected to a pipe system, and the flow rate that results is dictate by the balance between the pressure produced by the pump and the ‘restriction’ of the entire pipe work circuit. There is a common concern about the restriction caused by the inserts (stiffeners) needed at joints. These restrict the bore, but they are so short that the the affect on flow is much less than it may seem. For our final graph, we consider a pipe circulating with a fixed-pressure electronic pump (Alpha etc) The above graphs show relative changes in flow rate that would result from a fixed pressure. If the pipe chosen were too small, then a larger circulation pump may be needed in an attempt to compensate for the extra restriction caused by the small internal bore. The point here is that by choosing plastic instead of copper of the same nominal size, the system could potentially suffer unless the sizing is checked. There is of course no problem using plastic if it’s the right diameter. Indeed, 28mm plastic may be an ideal choice for the connections from a heat pump simply to minimise noise transmission. The best final solution is often a mixture of both plastic and copper for a multitude of reasons. All this emphasises how dramatically the wall-thickness affects flow rates and pump pressure requirements, but how does this translate into reduced COPs? Scenario(based on something I observed on a barn conversion) Let us consider a radiator at a far distance from the heat pump. The flow-rate relates to the pressure drop, which relates directly to the pipe-run length, and of course, the required flow-rate relates to the room size (bigger the heat demand, the more flow required). In this instance the room is large. The default pipe size choice would be normal 15mm (outside diameter), but if the sums are done, it may become apparent that the choice should be between either 15mm copper or 22mm plastic. How could a pipe with too small bore affect the COP? Radiators should be balanced, in general by throttling valves (lockshield) on smaller radiators, and those with shorter pipe runs. However, this is actually quite a difficult thing to achieve with a heat pump because the temperature difference (water inlet to water outlet) may only be 5 degrees (°C). (It’s much easier to measure and adjust when the temperature differences are larger). It is not ideal, or easy, to have to throttle most other radiators on a system, and there is the added risk of the circulation pump not being big enough to cope. The likely result of any ‘restrictive’ pipe-runs would be a reduced flow rate to the radiator. This would result in a considerable area (the bottom) of the radiator being cool, and a reduced heat output to that room. The obvious action to redress the short-fall of heat would be to increase the flow temperature by increasing the heating curve setting of the heat pump. i.e. increasing the flow temperate from say 40 to 45°C. Now the heat pump has to heat ALL water to a 5 degrees higher level. This is likely to reduce the COP by 10 to 12%. This all indicates that one must never assume copper and plastic are interchangeable without considering the pressure drops and diameters. That aside, we have also highlighted the importance radiator balancing. Ideally the pipe runs to radiators would be laid out, and bore sizes chosen so that the flow rates are naturally about right without the need for much valve adjustment. A little extra work on the design makes life much easier thereafter. Anyone intersting in further reading on water flows – this site is very intersting http://www.johnhearfield.com/Water/Water_in_pipes.htm Here you can enter pipe sizes and find out the pressure requirements to achieve a certain flow rates.

I could not help noticing that our heating has not come on fir the last few days, currently 8’ outside and house still 21’, only heated by incidentals and retained heat. ( a storm is brewing so I might light the woodburner for that “caveman” feel after I walk the dog in the rain ?).

@nodI had always been told 3:1 sand cement base then 4:1:1/2 sand cement lime for the top coat. Is that correct ..?

Interesting read, and certainly can't comment on the cost argument, but thought I'd share our experience. We moved in to highly insulated new build one year ago. I'd describe it as a semi-passive house in so far as we can normally maintain around 21c down to about 8-10c outside without heating, and then with very little until it gets towards zero. It's a fairly large property with Samsung 18kW ASHP. We previously lived in a new Persimmons house (and that's a whole other story!). What we've noticed: When you walk in to the house, it never has the familiar odour that most homes do. It just smells like the outside. My wife's a keen cook. The kitchen is designed without a hood, but any degree of smell in the house clears within an hour completely even though the house is open plan. We live in the country but its amazing how many pollutants the filters remove. Especially when neighbours have their log fires lit! Anybody with hay fever loves our house. They get instant relief from the moment they enter. We don't suffer from cold spots in rooms, or rooms that are a different temperature to others. Cloths hung inside dry far quicker than in previous houses. The house humidity is very stable all year round. During the summer when it was 35c outside, we were able to maintain 26c in doors with fresh air - heat recovery works both ways of course. When the outside temperature drops at night, the MVHR goes in to bypass mode with boost to help remove excess heat from the house. Throughout last summer this was a God send, especially since we get considerable solar gain from our windows. I've configured the unit to drop from it's regular 58% to 30% overnight. As others have said, the standard setting is unnecessary over night both from a power and noise point of view.

Decent bead of CT1 all round about 20mm in from the edge and nip the bolts up. Level it across the back then tighten, wipe any excess CT1 off the pan or tiles and the leave for 24 hours. Then go back over with a decent LMN silicone of your choice.

@pocster is having similar wall hung pan issues at the moment but his frame and pan are both Geberit. Hopefully your fixing inserts fit the pan fine? I'd CT1 it assuming your wastes behind are all good and leak free then the Geberit frame is pretty much bullet proof and accessible through the flush plate for maintenance. If those wastes fail then it's tiles off and cut through the wall board time anyway! I was particularly careful testing before boarding over, not least as I had a two different makes, "wrong way round" F to M joint where the grey meets the brown, solvent joint (done with pvc gap filling cement then CT1'd over): I even mocked up a pan to test the flush etc:

The design looks lovely I really like the style. I think £300k is tight given the complexity of the building. You could do it for this if you’re content to live in a building site for literally years on end. We’re 17 months into our build and it’s really dragging on. I can’t imagine the stress if we hadn’t aimed to build a €220k house within our €300k mortgage. (I think we’ll end up at about €280k by the time everything is actually done) You have lots of unusual angles and junctions and the surface area of the house is quite large for the floor area. In short unless you buy excellent windows, put in lots of extra insulation and are very particular with the workmanship you might end up with an expensive house to heat. In terms of size I certainly wouldn’t make it larger, possibly smaller and simplify the shape of the building. Reduce the external wall surface area and all the hall space and other dead space. If grandkids do arrive simple bribery will certainly suffice! Good luck!

We do hope to get this right first time. Luckily we hope our needs will decrease rather than increase and part of the justification for keeping it modestly sized is so we can stay in it for years to come. We're in our forties now, so trying not to get too hung up on stair lifts and zimmer frame practicality just yet!!

Build the house that meets your needs for the next 20 years not the one you dreamed of 5 years ago. Smaller house = less cleaning, heating and more money and/or time to venture elsewhere. Grandchildren between the ages of 10 and 20 will consider a night bunked down on your largest sofa with the TV remote to be an adventure, not an ordeal.

One option for you may be to keep the smaller size just but future proof the house for future easy extension should you wish to make it bigger. for example assuming it’s a concrete foundation, perhaps pour an extra 15sqm at one end of the house, at nominal cost at the build stage, and hide it under a deck or whatever. Make sure you have a layout that lends itself to adding on easily even plan terminated pipe runs etc so if you do wish to extend you could do so very easily. I have seen roof areas above garages done like this - built in a way that lends itself to easy future conversion. With my build I had the choice of a bigger build lower spec, or a smaller build with better spec. I went for the latter as my build is to live in not to sell.

I have a fairly large scale M&E company. The merchants to online suppliers will vary, even spending as much as we do sometimes you will see online prices slightly cheaper for the odd thing. I think the key with the merchants is about forming a relationship and understanding the value that this relationship can bring, especially with the independents. I would suggest speaking to your local merchant and asking to speak with the rep about a project you have coming up. Get them involved and get them to help with the sourcing or products and options they have a wealth of knowledge on products alternatives and relationships with the manufacturers. I know if i call an online company for a favour because i missed off a bit of stuff or ordered the wrong item its going to be a hassle i know if i pick up the phone to my local rep he is going to make it happen as we have a relationship. Stay safe .

I think it's a lovely design and fits in well with the plot. for an initial concept design I'd say it's a great start! but, obviously circumstances differ, when our architect said he was concerned about the budget for the size of the house we're planning I just said we'd build it in stages and finish bits as and when we need them. e.g. the basement won't be finished until way down the line and the room above the garage can be done at a later date. etc. that way we managed to convince that we could build the house we wanted for the budget we have. either that or he just gave up caring! at the end of the day, in my opinion this is, it's not the architect's responsibility to get the house built to budget but yours. so if you think you can build a bigger house for your budget then you need to make sure the architect accommodates those wishes. looks great though. can't wait to see how it all pans out.

Don’t underestimate the amount you can save with good planning and tackling things yourselves Your part way there in finding such a wonderful plot

Thanks!! I'm still in awe of the build costs you achieved, I only wish I had your ability.

Our specification was a luxurious Master Bedroom and Master Ensuite. That bathroom is more important to us than the one downstairs. The Master Bedroom exits through a Patio Door onto a veranda, partly covered by the roof. It sits over an outdoor covered seating area that adjoins the South-facing Patio and is screened to the North for 2-way privacy. The 2nd bedroom upstairs was, for us, the bedroom that would be used by a visiting Grandchild. We don't yet have Grandchildren, not confirmation that we will ever have! I'm not sure what that room will be used for if not! Originally it was assumed that it would share our upstairs Bathroom, but I said I wanted at least a WC in that room. There has definitely been caution with sizing, hence no Shower, which runs the risk of being a bit of a waste. Yes indeed, if the occupant of the upstairs Spare bedroom requires a shower, they do need to use either our Ensuite or go downstairs. One of the compromises we made to gain a good sized Master Suite, whilst staying within the Architects 'sensible' floor area.

First error on my part, I should have pointed that out. The top 2 drawings are shown true North. The Site Plan, perhaps against convention is not. The design does seem to consider the path of the Sun really well actually and perhaps with that better understanding of the correct orientation, it might make more sense. I hear what you're saying about the shape of the building. I wanted something that would be an interesting shape, we specified that we love internal angles, this certainly brings those in droves. Here is a couple of 3D views, but keep in mind they are very early, still work-in-progress. Further comments from me will follow in line...

It looks like a fabulous plot and a nice home If you look through the back posts on here You won’t find anyone complaining they built there house or a room to big If you have concerns about the size of the house It may be worth sacrificing a luxury item or two for a few more m2 300k is a very healthy budget for a house of this size

Oh I wish. I think we are on course for the entire January to average less than 0, with -16 the record one night. The weather man just told me tonight is likely to be the coldest night of the winter with "minus double digit" temperatures widespread. Definitely permafrost set in which will take a while to thaw. I think we might get up to about +4 by next week. We went for a walk by the coast here today as all the local footpaths are far too slippery for nice walking at the moment. Snow lying right down to the high tide line.

To clarify then... The ASHP can produce UP TO 18kW of heat, but would never need to produce anything like that normally. At 8c it's real life continuous use is around the 1.5kW mark. Right now it's about 1.5c outside, about 60% of the UFH is on + first floor radiators and it's consuming 2kW with a flow temp of 37c. At -4c I've seen it rise to 4Kw. I believe the max it can draw is 5kW. Obviously it will vary according to load. The heat loss calculations for the property show a 7.6kW requirement at -3c. The design model uses an average COP of 2.68 at -3c and season average of 4.31.

You are going to need a waterproofing system for those outer walls, this needs designing now with your icf supplier, and building regs designer.

Overall I like it. For my mind the living room is a bit small. I would be tempted to make room (10) the dining room, then make kitchen slightly smaller and living room bigger. It might not be possible in your case but if room (10) became the dining room I would also look at making it open plan to the stairs/corridor (4). Corridors are a waste of space in my view. If you want to make the house bigger now there are things you could delay if the budget got tight... For example both garages and the terrace over garage 6 could be delayed until later. Plus some of the walling near the patio? Alternatively consider what you could add later to increase space. Conservatory where that tree is in the crook of the L?

I see lots of wasted space and a bedroom upstairs with no access to a shower unless they go downstairs ..?? Room 2 has to go to Room 8 for a shower ..? No master bathroom or bath other than main en-suite ..??

Yes - sharp thin blade will take it off as will a guitar string as a cutter.

I am struggling with orientation, particularly as floor plans are drawn with a different orientation to site plan. But assuming site plan is drawn "north up" and I have not got confused rotating floor plans to match site plan you seem to have the living room and kitchen in the north east corner of the plot, missing the sun, and missing the views over the garden? That would be my one criticism of the architect, not keeping a consistent orientation on the plans and not marking where north is. The "non 90 degree" angle between the 2 wings will not help the budget. If you are thinking of future extension possibilities, have a think about making the layout and the building construction such that it would be easy to add a second storey to the other wing as well.

The buildings walls will be retaining using steel reinforced concrete within ICF. I haven't decided whether to go for eps or woodcrete yet. I will be relying on a structural engineer to provide the exact specification of the wall.

I think it suits the plot very well, she's done a good job. Though it's hard to tell without elevation drawings. We started off with an aim of a 4 bed within about 180m2. That's crept up to 200m² because of a large open plan space. Regarding bedrooms, our architect sticks to a min of 3.3 X 2.7m for a double bedroom. Our. master is 4x4.5m Your other rooms are very similar to ours. If you visit a developer's 4 bed show house you'll soon see your design is more than generous. Would it be possible to square off the transition from one wing to the other? The extra corner is not only more complicated, it removes habitable space and is a bit less thermally efficient (you want a smallest surface area to volume ratio practically possible). I think there is scope to simplify the design and increase floor area to 200m² and stay within budget. You'll get much more value out of an extra bedroom or office, than a fancy kitchen.

What did the builder do with regards drainage. Unless there is something there then with the rain falling in such a large area its always going to get damp.There should have been weep holes in the block and brickwork to allow the rain to drain out. As it sits it's building up and soaking through and forming the damp patch. I would go with the easy fix as he has mentioned and drill a few holes to let the rain out.

Foundations sat in water is not a problem (I have a high water table), with our foundations I had to dig a small “sump” next to the foundations to enable a small pump to drain the water before the concrete was poured.

I’ve only put my mvhr on once for about 5 hours . Went out , came back - I could feel the difference.

Thanks @troggy02 thats v helpful. What make and model unit do you have and who did the install and design?

It's warmer where you are it's now 2 degrees here. I'll be lighting the woodburner later.

We have the house at 21c, but note, the thermostats for the UFH have to be at 23c to obtain that. We have a couple of accurate weather stations and traditional thermometers that all confirm the 21c actual temp. I think the room stats just aren't that accurate. Energy wise you're in our ball park. On a very cold day (say -3c) we could consume 40+kWh to heat the house and water or more. It's worse when between 2 and -3c, humid and ice forming on the ASHP due to the defrost cycles. Either side of that its pretty efficient.

Thanks Wozza! I'm sure if I have a demo I will love it. Just wondered what it's really like from people who are actually using it in their homes. Of course, it has to be people who cook a lot of smelly foods like me! ?

I’d just arrived at same conclusion!

@Onoff I’m pleased to say that the pan attaches to the (buried behind tiles) frame without issue. It’s just a case of finishing it off, where to mastic/CT1 and where not to.

I would not bed on CT1 as if there is any future issue with the pan or plumbing behind you will wreck the tile. Just silicone will be fine. The frame does the job of supporting the pan, not the mastic.

Sorry. @tonyshouse built his place using brick and block and is a very strong advocate. It is worth having a read as his place was very carefully detailed and performs very well. I don't have a preference for build method.

You have an external layer, let's just call it a 'rain screen' for simplicity. This forms the outside protective layer against the weather, which could be your outer leaf of a brick & block, metal cladding, or timber cladding. Behind this, you'll typically design in a way for any water ingress to get back out of the building. Typically this is some kind of free space. However,it may also be achieved through use of building materials like a wood fibre external wall insulation with a lime render where is moisture does penetrate the outer skin, the material can buffer that moisture ingress and then naturally dry out when the weather improves. With a timber frame, which will typically sit behind such a screen, build method and detailing is important. The traditional and basic way to build up a timber frame is, from the inside: Plasterboard Vapour check - usually a membrane sometimes just a plastic sheet sealed at the seamsand sometimes a more high tech membrane that has a variable vapour check behaviour. Timber studs with insulation between the studs Frame sheathing - OSB/Plywood Breather membrane ventilation cavity - minimum 25mm outer skin. Now, there's a myriad of variations to this so this is just a basic illustration. The vapour check prevents warm moist air entering the timber frame/insulation layer. If it was allow to get in there, at some point the wall temperature would be cold enough to allow the warm moist air to condense, which would cause damp within the frame. The OSB/Plywood and breather membrane are there to allow some moisture to pass from within the frame to the outside, to prevent a harmful buildup of moisture while also providing some protection against ingrees of excess moisture from the outside. The problem as has been found in many timber frame buildings built in this traditional way is that the vapour check gets pierced during 1st and 2nd fix and not sealed up properly again. This allows the vapour to pass into the frame, causing excess moisture through condensation that can't be dealt with by typical insulation materials like glass wool. This moisture stays in the frame and causes rot over a long period of time. So your basic protection for the timber frame is proper detailing of the vapour check layer and your external membrane. With materials like wood fibre and sheepswool, for example, research has shown that because they're hygroscopic, they can soak of excees moisture in the frame (glass wool can't so the moisture condenses onto the material) and then pass it out to the atmosphere to even out humidity levels (a little like a hot item will cool down to atmospheric temperature). Because these material regulate this moisture in the frame better, it is better for the frame and actually reduces moisture levels with the frame long-term. This type of system build is approached slightly differently but again detailing is key. I've attached a document by BRE that talks about these natural insulations and how they can prevent bacteria and mould build up. The paper focusses more on vapour permeability but hygroscopicity is just as important. BRE Information Sheet Natural Fibre Insulation - IP18_11.pdf

What frame ..? And did it come with a gasket..? If not, decent bed of CT1 and then use a replaceable silicone all round the rest of the pan when that has gone off. If there is no gap under the pan then use a 2mm packer wrapped in cling film to make a gap at the bottom of the pan /CT1 so any leaks in the future are visible.

It will be slower. If you want quick to watertight then timber frame is your choice. What is the driving the desire to get to a fast watertight shell..? This is pretty much where the cost / time / scope equation comes in - if you want quick and the same scope or quality then it will cost more. In terms of outer leaves, the range is from around 0.4 at the aerated block level to 1.6 for concrete heavy blocks, with bricks sitting somewhere in the middle around 0.8-1. Now consider that your insulation has values of a tenth of that lowest level, and you can see that actually unless you go for a super light - and expensive - block you will be shaving less than tenths off the wall value. What you need to do is increase the ratio of the upper and lower values so increase your insulation layer as a proportion of the wall build up. The average house (140sqm box) has three layers of insulation. A 70sqm floor, a 70sqm attic, and around 150sqm of wall. The insulation cost of the wall insulation at 100mm is around £550, the cost of it at 125mm is £630, at 150mm is £770. So if you factor in a slight increase in cost of lintels and ties, it is probably circa £500 on the cost of the materials. For a building that now has a significantly better uValue for its walls and will more than reach your SAP score. You can’t get the renewables to do the same for less than £2k I expect and you will not recover the additional cost through any sort of FiT or self usage in 5 years.

You will be slower with thin joint and brick. 1. Thin joint uses glue, bricks use mortar. Your brickies will need to alternate between the two, and can’t “use up the last of the mix” on 15 blocks at the end of the day. 2. Wall ties take seconds to place and are cheap. Start using helical ties and you’re needing the tools plus they take time to install. They are about 10 times the price of standard ties too. Most BMs don’t stock thin joint glue so when you run out it’s another delay. 3. Labour doesn’t know what thin joint is in the UK. Expect a lot of waste, broken blocks and excessive use of materials - they are learning on your job and will be slow to start with. Coursing will need to be accurately managed, as will lintel placement. 4. Contractors price what they know. How many bricks and blocks they can lay in a day. They can do those calculations on the back of a Greggs bag ... new stuff they will guesstimate then add 20% for hassle factor. Thin joint isn’t your answer here ..!

Just watched the latest episode and you are all a bit curmudgeonly. Pioneering spirit and a very nice and interesting house that ticked both of their boxes - albeit not sure what happened in the year or so in the middle.

Hi Steve. This is a bit of a puzzle as there is not much info, but enough to spark a bit of geeky interest! Based on what you have posted so far re section size, forces and so on I can sort of see how something like this may work with the wind bracing and so on, but you are going to need a good bit of space to form some of the (assuming bolted) connections, you need to look carefully; if there are window details, a limit on the floor depth and so on. This could be a problem? What you have posted so far looks like the maximum forces and maybe the fabricator needs more info. Take column 2 supporting beams 2 & 3. Simplistically these beams have a bending force at the ends.. the moments - kNm. Beam 2 moment loads the column about it's "strong axis" and beam 3 loads the column about it's weaker axis. If you combine these forces with the torsional moment plus the vertical load (V) then the column strength capacity looks debatable to say the least. What the SE may have done is to model beam 3 with a pinned connection at column 2 so it does not transfer a moment (axial load ~V) but at the other end (at column 3) modelled a fixed connection and provided this set of more onerous forces rather than the different forces at each end. This may partly explain the fabricator's response. The connection at column 2 in particular is relatively complex and will take a good bit of thought to account for all the combinations of forces. Looking at this I think it's likely more than a ten minute job to design a connection that will be as small as you can get it and thus maybe fit in to the space you have available? You could end up with some pretty big bolts, thick end plates on the box section, stiffeners etc, nearly get it to work then find you have a bolt clash or the sequencing of the works stuffs you in terms of the order you connect in the various beams. This could be a communication issue but I would just ask the SE roughly what sort of connection and size and form they have in mind. Also ask if they can do the heavily loaded connections with "ordinary" bolts which a local builder can manage ok. Or does the SE think some kind of tension control (HSFG) bolt may be required which requires more specialist knowledge and tools to install. Make it too complex and most small builders will back off or add a lot to the price. I dabble a bit with connection design so would be interested to see the solution and how it all fits with your structure.

If it’s just moving paper the online solicitors are pretty cheap

I thought she would have been gone by the end. He just came across as the sort of guy who would be sending her an email to book in lovemaking on Wednesday week at 8.33pm. He would then be late, because he would be probing his temp sensors. (I thought she looks hot)

Heating is one part of the equation. DHW and general appliance use will be a massive chunk of the energy consumption. No provision for them? They spent a massive sum of money to reduce only part of their energy consumption! Seems to me that the geezer didn't take a step back and look at the bigger picture. This is more like an idea he was fixated on and everything after is geared up to prove himself right. Yes, the principle works. But was it worth it and did it make sense. I would argue no. I think that the builds on here would be more eco than this one?‍♂️

feeling very sorry for the wife.

Hi and thanks for the welcome. Its a two story build but on a small plot next to a bungalow on a sloping sight so have to dig down a lot. So have gone for the isotex insulated raft and blocks as some is a retaining wall. So not low embodied carbon but hope to have very low emissions. I will up load some plans and pic later today we just managed to get the raft in before Christmas after shifting 400 tones of soil. 2202 - (BR-)04A (1).pdf 2202-(BR-)01C Floor plans.pdf

There is 3 days work there maximum - it’s a conservatory base in effect and they don’t take any longer and tbh it sounds like you’re digging in garden rather than patio which is easier. Bricks and mortar are £150, concrete (on a volumetric mixer) would be £350, 6 sheets of EPS £100. If that was more than £1500 tops I would look elsewhere.