scottishjohn

I think the point is that IF it did get wet underneath --flood -etc then you need an air flow to dry it out or you would get mold--so it needs to be hollow + vented or SOLID like concrete

I find that hard to believe as all types xps .pir pur +phonelic are closed cell foam eps is the least waterproof of them all and this company is showing PIR is ok for use in under slab uses https://www.ballytherm.co.uk/floor-insulation/

you would have no problem with SEPA --salmon cant run up that waterfall

so when you fitting the turbine to it? or even an over shot water wheel LOL

one I am chasing is 110m ASL

moisture is not the reason -none of them absorb moisture and all have good load qualities big difference between eps 0.034 and phonelic 0.020 --about 58%difference --

eps 0.034 pir 0.022 phonelic 0.020 why use eps at 300 mm when you could use either of the others at much less thickness and get same value Or conversely use same thickness and get better value ,as from my reading there is always a fairly major heat loss through the floor slab Is it purely the cost difference between types -or is there some other reason

sounds like you need a planning specialist on this to me certainly what i would take some professional advice at this stage but that just me

thank you --then you have answered my question It is not a system that you would design a house around when starting form green field site ,that is enough for me , The man who is making it would not use it as primary heat source in a new house if mains gas was available --the usual energy source for comparison on any system so no matter the current discussion on output etc ,etc - its no use to me if it not better in any tangible way but may have uses in retro fit applications I don,t think anyone is slagging the actual product , but it is the real world application +costings when compared to other systems

and of course you had it tied down with the compressed gas hazard stickers on the car?

you mean LPG --not mains

could be ,but i,m thinking to 10 years from now when PV panels + battery storage could be very much cheaper and carbon base fuels are hit by taxation

bottom line is nexgen needs to propose the ideal whole house heating system that would be more economical than passiv slab +ashp wet system etc specification from top to bottom so we can see how it might be used in a new build to best effect and then compare overall costs on initial build and running costs If they cannot do that then --they have not looked at it close enough to claim it can be a REAL whole house system and until they can show that then it will never become an alternative I can see it might have some retro fit applications to solve some problems ,but I need convincing that it is a REAL alternative to wet system . maybe solar PV + batteries have to be included in this system ? I want them to succeed

a lot of insurance companies now will do insure garages etc to use oxy/act for heating purposes -due to fire risk ,so now induction heat sources are preferred by them https://www.ebay.co.uk/itm/173957945667

https://hobbyweld.co.uk/ there are others who do the same -- you pay a one off depsoit --then just pay for refills I became an agent --when i got fed upof paying £600 per year ,just for the rentals of my ox .acte ,argon and argon miX bottle as my usuage in last 10 years has been very small so full size bottles too expensive on rental yes you pay more for contents -- but still works out much cheaper if you just now and then -- if you use 2 full size bottles a year --then maybe usual rental system may work for you --If not then smaller size bottles where you only pay an initial deposit contents will be at least twice or 3 times the cost --but no yearly charges or delivery costs and now all bottles are barcoded they know if its a genuine bottle with a valid rental agreement --so the old way of just getting a bottle swopped does not work anymore --EVERY bottle has to have a rental agreement with full size main stream suppliers I don,t have acet any more --just use oxygen and propane for heating or burning things off ,as all the scrap yards do acet is expensive and bottle deposits are expensive as well

I used it close to 20 years ago as it seemed the easiest way to stop the cold draft in the crawl space under house getting to the underside of the floor-- i check it every year or so and still there and all joints still happy --had to retape a couple over the years - the thought of trying to cut and fit normal foam from the underside --did not appeal as i could only get the roam sheet under there in small bits through the access hole and the cost to get it spray foamed was too much for me + i would never be able to get at any of the services once it had been done --different if it was planned that way when house was built--retro is always a pain ,so compromises have to be made

I have used multifoil blanket under my suspended floor as it was the easiest way to insulate the whole floor and deal with all the wiring and pipes etc from original build and have to say it seems to work very well as it has air on both sides --not being compressed in anyway

what would you want to braze? last thing I coated used brazing rods for was diesel injection pipes that got rubbed through on diggers from local quarry --and that was years ago -then i swopped to silver solder rods much easier and neater. and then i got a mig welder about 25+years ago followed shortly by a big HF tig --never missed using brazing rods

gas less mig are total crap -IMHO you need shielding gas and you need to clean at least 25mm either side of weld on both sides of each piece if possible if you want a first class result - any undeseal or paint or oil --anything that is too close will burn and give off gases which will effect the weld - -thats the whole point of using co2 /argon as the shielding gas yes you can weld if its not perfectly clean with mig --but its not as good and spits and pollutes the ceramic shield TIG is even fussier than mig with a TIG you can weld or braze any type of metal together,gold ,copper ,silver ,lead ,alluminium anything -but it is very slow compared to mig ,up to 3mm in alloy plate you don,t really need a filler rod just melt it together its gas welding with electric really

use nexgen panels on the ceiling .????? that might be a good use for them in this instance

or stick welding is very difficult on thin sections like car body work --so is never used for anything but heavy gauge welding ,like bridges --over 8mm usually you can do a single pass 6mm weld or more with a mig machine TIG you can weld fag paper thickness ,,when you get good at it --much slower than mig +stick years ago I bought a miller syncrho wave 375 amp tig unit --to make alloy inlet manifolds where the flange was 12mm and could do it in one pass and can also with dif torch weld 0.5mm alloy --on a good day -- also had a alloy mig machine to make alloy car transporter bodies --but alloy mig is not very flexible and must be used with a push +pull wire feed or a spool on gun. modern invertor units for small sizes are very cheap now most of the jobs people bring me for alloy welding are wanting miracles --alloy sumps or very thin alloy casings in many pieces - not a problem if they want to make a jig to bolt all the bits in place while i weld and cool them or an alloy cylinder head that corroded to buggery --again not a problem --but after i grind all the oxide out ,then weld it up and themput on the miller to machine the face back true not just a 10mins job -- the thing they don,t understand is that to alloy weld the whole article to be welded must be preheated to over 200c -- best one i did was head fromn a 1925 rolls royce --,basically cast iron head --+old age and no antifreeze not another one on the planet --he tells me --can you fix it -- yes but it was not quick or cheap

being fairly fluent in both tig +mig the question is do you need to weld alluminium or s/s ? if so then tig s only really way and that is only good if you are working with NEW metal -not rusty things mig is generally far handier +easier for general purpose welding. stick welding is not as flexible or easy If you are contemplating welding up your land rover chassis --and you are keeping it --then don,t just buy a galvanised complete chassis unit and swop everything over -do it once do it right for a mechanic who has done one before its about 20-30 hrs - but very simple work with new chassis on oil blocks next to old vehicle on blocks --unbolt the bodywork --leave to one side then just swop everything over I,ve been here before repairing out riggers , patching up chassis legs then its a complete back end section --you just keep chasing it around and its still a rust bucket get a new chassis unit --fit +forget

you need harry potter and his magic wand then

I am still awaiting the answer to my question 130sqm house with near passiv insulation levels heat load of 2400kw per year why should i use nexgen instead of UFH and more importantly what would the cost of a system with controls to do this and total electricity required to accomplish an ambient temp in house of 22c can it use a mix of solar pv and mains as power supply for winter when solar pv cannot provide enough energy to run the nexgen panels you say it is fitted like wallpaper --that means it is not behind the wall but on the habitable side of it ,so would need to be covered by something ? do you have an installation video ?

Ok make your case for using nexgen instead of wet UFH heating in a NEAR to passiv house 130sqm heating load calculates out at 2400kw per year . I would like not to have spend loads of money on an a ASHP and UFh heating system and possibly run it from solar PV and switch to mains when not enough PV inthe darkest part of the winter and at night