scottishjohn

remember to add the cost of rendering on block wall and coping stones for it --unless you want to look out at a scabby bare wall spoiling the project with an industrial wall seems foolhardy to me -# its your house !! have you priced dry stone dyking costs locally ?

you still end up with an ugly block wall --hardly something that you will want to look at from inside the house for very long so you got to allow for rendering or something as well It a no brainer to me use marshalls croft wall blocks --done in a day and finished in one go -presuming you have a suitable foundation for them ,but you need that for any wall it does not have to be straight either you can have some nice curves in it

I only had 2x20 tubes thermomax --and they boiled 300 litres --so something wrong with your set up if you never got very hot water

or something that looks pretty like marshalls dry stacking walling --do it yourself in no time https://www.marshalls.co.uk/homeowners/view-croft-stone-garden-walling the layer above sits behind the lower layer so it locks together i have used it ,water drains out through the gaps as well so no worry about a tsunami of mud

you buying seconds?

evac tubes or panels / how many --what size cylinder ? what controller can,t be that hard to borrow a roof ladder or make one out of an normal ladder for that job or just tie a rope on it and throw it over the roof and secure on other side - or rent a cherry picker? I saw a danish one where he mounted panels on the wall vertically --this cut down summer heat a bit to stop boiling --but raised up the winter output +he could get at them very easy certainly will be considering that or a ground array on next house --getting too old to go on roofs I don,t bounce like i used too last one was on flat roof on garage on frames and set at 54 degrees same as our latitude so fairly vertical then

it will do it all !! whats the problem with it ?

I bought an arrow cordless one when i di my underfloor insulation fitting loads of mulitlayer foil insulation that did speed up the job when lying on your back in a crawl space

yes you can but ti drops the payment you get for the ASHP --cos rate for solar is a lot less than ASHP chances of some one coming is virtually zero -

maybe a rough cross sectional drawing would help

is the ground behind it flat or does it go up at an angle --and what angle?

that changes things alot--whats it holding back

can we have drawing of what you have please ? are posi not deep enough to make holes in for services? where is the insulation for the flat roof ?

just to add another dimension and possible way to do things I ran solar thermal evac tubes on my house for years and I found them very good for dhw and indeed also helped ufh they were removed when i went ASHP-cos i would not get same RHI if they were fitted nothing to stop you fitting solar after doing RHI claim ? anyway what i had was unvented 300l tank which had solar coil at bottom ,then UFH coil in middle of tank dhw at top --with cold mixing on out let --so i did not waste the heat i stored by adding a lot of cold at taps and the parent volume of the tank was heated heated if needed by a lpg boiler In truth it was not a large enough tank cos i could boil it in the summer just with2 x20 solar panels - I fully understand the heat loss argument I ended up surrounding my tank with 50mm pir pipe insulation segments --stock item as tank was 500mm this made a major difference to heat loss --but made summer boiling worse .LOL so only real downside was tank too small 80%of the year i got all dhw from solar +some UFH --which due to old house design i needed more than you would with modern house --overheating of house was and never is a problem If doing it again i would have at least 500/800litre tank with same coil configuration and as tall as you can fit --taller+ larger if you can accommodate it and maybe UFH coil closer to bottom I not looked at it yet but maybe ashp coil in tank at that level as well rather than heating all tank--that will be investigated once i have the plot sorted +house design If you have PV then maybe elec element close to top of tank to boost dhw when solar cannot _+ If you have free energy --it will fill the tank downwards and allow solar coil at bottom to work at low temp in winter when you maybe only get 30-40c on bad days -which with passiv type house etc is plenty for UFH,as most of you are saying your floor is running at 20-22c + 150mm of pir around it and all pipes lagged -above 150mm the extra cost /insulation is not cost effective-so Kingspan man calculated taller means more thermal stratification to get best solar gain and DHW production and you do not want the water stirred up - solar coil would have a "top hat" over it with a pipe going to top of cylinder so hot water goes to top ,if hot enough first ,with side outlets at different levels so it heats where it can I know this tank sounds expensive --but balance that against cost of multiple sunamp units Yes PV can be used for other things ,but if you have space for both ,then your PV can do things other than water heating , solar thermal can do DHW-and some of the UFH I believe there is a good reason for both in a balanced system ,if space available for panels - I do not think that now PV is here that solar thermal is obsolete-it has a place along with PV what i have yet to find is a direct comparison of pv /verus solar --purely for heating water -on A DAY WHEN EITHER CAN DO IT I suspect solar thermal will be be better -as you make voltage ,transform +invert it before you send it to an element -got to be losses !! solar thermal is direct+ much simpler I think the previous posts over estimate the maintainence problems i ran mine for close to 20 years with no problems other than those caused by me in a round about way the boiling problems --due to too many panels and not large enough tank -fied a sensor which then allowed it to keep running -=-result all foam insulation on copper pipes melted off !!--so that was in excess of 170c another thermal sensor in another postion as a safety measure would have stopped that -which i then fitted apart from that I spent nothing on system when i removed it i found some of the tubes were blown --but i am putting that down to my major overheating issue --but even with 6 out of 40 tubes gone it was still working ok the cost to repair would be less than an invertor replacement .

the way i was told -long time ago was 3-1 is a pointing mix ,very very strong 4/5-1 brick laying mix ,depends on sand type as well yes plenty use 6-1 no problem - -but the problem with mega builders was I think it wasn,t even real portland cement ,but a cheaper type mixed with other stuff,then made weaker cos it laid up easier not the right thing for all weather building why would you use 6-1 --half the cost --thats why

any one where you can get people who work that hard ?

I keep doing the lottery --I really need all 3 pieces of equip tractor with front bucket + self loading pan mixer on the back ,telehandler+ man cage + 5ton digger I keep on dreaming

not convinced you will ever get celotex packed in an i-joist or anything as well as this integrated stud. you could of course use your I-joist and spray foam them ,but a different way and no metal in wall

I know first time Iwent ot kenya big game fishing in1982 we would look for the birds to find the fish and rom the flying bridsge you could see the sholas of tuna would strech for maybe 10-15 miles and you just criss crossed them -to catch fish last time i went 5 years ago --all gone lucky if you find a shoal more than a few hundred yards long . that si the proof ir you needed nay that we as humans are too many and using up all the worlds resources quicker than nature intended or can replenish them reduce population --you reduce ALL of the worlds problems how you do it is another thing which is why I am amongst the "doom +gloom old men " that can see no real solution other than population reduction or at leat hold it where it is and do all the other things as well I don,t need to surveys done by professors etc to see what has happened to the natural world in my life time , salmon stocks less than 10% of what they were in the 50,s ,herring fleet --gone -bees ,birds ,buterflies -etc etc . all of these are due to direct pressure of populaltion

which comes back to where i started - we as individuals can do SOD ALL to make any difference. the government has been trying to raise fuel duty,to encourage people to use less, now for many budgets and every time do not --afraid of outcry from population+ biz why are cars not taxed on BHP --not matter how you want to cut it -you burn energy to make bHP --thats physics so bmw m5 should by £2000 road tax--slightly cheaper than a 44ton truck and your super cars 600bp etc £5000 a year -if you can afford that sort of car -5k for tax is no problem ,and not just have high first year duty . no politics will control what could be done

the reality is it cannot or we would not be having the planet problems we are at this time . ye if we get a killer virus that wiped most of humanity out the planet would recover over time --so all the problems are man made and the human condition says people do not change their ways unless they are forced to people who believe they will are living on cloud or "never never land"

no they have a cheap energy supply and cheap labour all raw materials are a world price --they only things you can control as a country to make goods is energy costs and labour costs ,and taxation which is why there has been a shift in mass production from country to country since ww2, used to be japan ,then taiwan and INDIA at the moment it is china already the middle classes are wanting more money etc ,so it will eventually move to africa or south america --as wages rise in china

until they get cheaper ,by a margin ,which i doubt ,then without some sort of FIT -tax credit --what ever--it will still not attract the volume needed--maybe a zero rate finance scheme ,as i was offered for my If i fitted panels --downside was i needed to use 70% of generated elec on site-- not possible with a service industry - my south facing roof is 30.m x 16m--480 sqm --thats shed load of elc prod and i already have 60va 3phase ,so was possible to do- just i,m to old to get the return -

yes you could,and i am looking at that but also to be fair you should have a different FIT depending on how far north you are,due to reality of how much you can generate

so with the law of supply and demand you havejust given the reason why MCS charge what they do to make it viable for them to continue