scottishjohn

I just wonder when or if it will ever pay to go off grid -if it ever will -considering mains connection will £15K+

If you are going to dig a hole and fill with hardcore --just add some cement and make them concrete +level them up at that stage when concrete is wet -then blocks -no need for a wacker ? then

In the states and other places you can get 16ft long plasterboard -so they put it on sideways - and quite often just stick it --so no screw holes to fill

better make sure you get your stud work right EG make sure all studs are straight --that will be your first mission as CLS is notorious for not being straight these days or bowed in its length -go to bulders merchants and pick some up and look down its length If you want straight then use gyproc steel studding for stud walls

the real question is how soft is your garden - will it sink and how much will the floor flex if you skimp on supports nd how big a concrete pad under each block- or no pads just set on earth ?

and this isi a load of crap yes closed cell will not pass water and it is stuck to sarking so obviously there can be no condensation on sarking or osb sheeting - and if its a cold roof there should be ventilation at the eaves and or up the cavity wall your batons and roof paper on top of sarking gives ventilation to outside anyway read the small print in any house survey and it will exclude any areas that cannot be seen without dis mantling any thing

surely the answer is to foam between rafters and leave edge of rafters exposed allowing viewing and breathing of the wood and no one is going to fill rafters up too the top anyway with closed cell -too expensive and no need and on anther note how would a building surveyor when checking a house with modern insulated vaulted ceilings check the condition of the roof- they cannot so same should apply to them

I understand what you say but a suirrel could run up any sort of pebble dash on a house anyway if it wanted you could put a steel cone shaped ring around tree below the nest site which would stop this anyway

swallow box on a tree --3-4m high up with a protruding ledge over the top and down the sides ?

why can you not share? --under the eaves is where they always want to build their nests-not inside your house

I hear what you are saying velox is diffferent in that the woodcrete does not penetrate the concrete core( basically its woodcrete shuttering) -so not to looked at the same as durisol and isotex and again needs very little if any bracing as braces are built into the wall construction before concrete pour

it seems I have been misunderstood I never thought that having a concrete /granite wall inside the house would store enough energy to provide heating in the winter with no other input that would not be possible this started off with my suggestion that the second floor could be supported on block +beam or hollow core planks and that would give a thermal store to help keep house at a stable temp yes I might have a feature wall of granite where we will have a large window downstairs to absorb some of the excess heat from direct sunshine during the day and release it back in the evening . house faces s/w I already get a smaller version of that with present house which has tiled floor where we have a double sliding window again i think i have not been clear or you have picked me up wrong my 0.7m granite outer wall will have an air gap before the new house built inside which is where the insulation will be as normal practise not expecting the outer wall to do much other than slow down heat loss or gain and far better than some thin exterior cladding or screed as for thickness of insulation "kingspan tech man " told my anything more than 150mm of PIR is basically a waste as extra value gained is so small above that it would never pay , this was when i was trying to configure solar thermal a good alternative .as I already had a smaller system on my present house which could only be done by having very large storage(15-20000litres) in this country ,works fine in the alps with a fraction of that volume where they have bright sunny days all through the winter but not uk

my outer walls are 0.7m thick before i build the new house inside it

you will how fast the temp changes if all heating ceases the insulated one with a stone wall inside the envelope will stay warmer longer as it releases the stored energy /heat slower and it will be slower to heat up for same reason the modern passion for mega size windows + no curtains only make temp swings more violent between day and night and need for air con more probable -- that uses energy

but you need energy to to raise or lower the temp of anything - and stone whilst taking a lot longer to heat up also takes longer to loose it once warmed up to target value and whilst most will say there is no insulation value in stone it does have slow transfer properties does it not therefore have a long decrimental delay in heat transfer ? the magicword for those not subscribing to the heat sink camp the reason in hot countries they build stone/clay houses with thick walls to control the diurnal temp swings in some countries

where I got the idea was from an article If I can find the article again i wil post a link It was an office complex in uk with a large car park -pipes buried not that deep below tarmac --a vast area which the water mix was pumped in closed loop around to what could looked at as large well insulated sub basement filled with granite sand and small stones -and a closed loop taking heat from this to the heating system of the building all summer it heats up and is then used in winter obviously when ground temp is lower than the heat sink - it does not circulate . have you ever touched tarmac when the sun is shining

that is why I only went to80c -to restrict the evaporation of the water from both trays and as both had water the level in the trays at end of test were very much same as at beginning of test quoting you (thats Why storage heaters work.) which is why i know stone concrete are good heat store and will smooth out temp change

when I was looking at solar thermal I did a test at home in the oven 2 containers one with water one with water and granite sand and 80c temp in oven the test was to see if I could use a large tank filled with water and rock to store a lot more heat -than water alone in same size tank-the down side was the limited heat input you could get from solar thermal -and then it also gives the heat out slower than just water -great if i had little geothermal vent to tap into or in arizona .LOL yes water heated up more and much quicker over the test period , a lot more but when i turned oven and then logged the temp drop the granite sand stayed well above ambient for along time compared to the water ,at least twice as long which is why I say concrete etc will act as a thermal store and level out temp changes in the building ,presuming its inside the insulated envelope ,which will make it also good in hot summers It also is why pass house designs often have an atrium with glass facing onto a solid wall to control big temp swings and I have seen some designs where they have holes this to me is why ICF buildings work as they slow the flow of heat in both directions all non poly systems have the insulation on the outside portion of the ICF wall for that reason and even poly types have the most of the insulation on the outside as well.

I looked at this 20 years ago and what put me off in the end was the fact they could not say for certain if one hole or how many holes would be needed to get the heat output ,until first one was drilled certainly where i am it would be into solid rock with 10m for sure so not a lot of casing needed . I agree about trenchs -most are not deep enough and to me is only suitable for wet ground and at least 1.5m depth -which I do not have and digging in boggy ground that deep will cause problems in keeping trench from collapsing at that depth freezing the ground shows they are not deep or long enough to recover from extraction of heat

no gshp will never be a good choice over ashp in this country due to costs and average winter temp here is 3c if it were like canada with -10 to -20 for 3 months --yes only place it might be is in a lake where you can just throw the loop in from a boat -but trying get down 1m + on rocky ground --not good If I was in the quarry with a 30m deep lake --then yes that could work

planning would be a problem i think and would still need batteries

what ever heating system i use it will gradually heat up the mass to ambient in house ,but take long time to cool down specific heat of concrete is at least 5 times more then water-so it will be a heat sink . will really depend on cost compared to std type floor -but i could end up with a 7m+ span -so maybe would do away with need for pillars or steels on ground floor ?

that should all sold by end of january and its close to 300ft below the house too expensive for piping

I got more roof space if needed as that was just one side I got a south facing shorter one as well and if really needed i got loads of space for ground mounted system i got wrong size it should have been 74sqm and i could be small on that as guessing how tall it will be --not done the calc 30degree pitch and 2m+ from wall head to ridge

no idea at this time until final design is completed as i,m building another house inside my granite outer structure/ TF is what has been suggested ,but maybe a block type and use block and beam for second floor ,which will add a nice big thermal storage to new house ? I,m doubtful it will be easy to get a TF kit that will easily inside thei old house ,as walls are unlikely to be true ,so maybe just build inside with block or ICF? no decisions made yet planning have eventually replied to me and are promising consent towards end of january then I get going with quotes etc