I have another question - the new part of the house will have subfloor insulation - maybe Kingspan AIR-CELL Permifloor ?? but the remaining part, 2 bedrooms and living room in 110 year old house has a timber floor with no insulation. There is a metre above ground at the highest point.
If we insulate this I can see that it would help in winter by stopping the heat getting out but what happens in summer? It is comparatively cool under the house in summer, wouldn't the insulation make it warmer inside?
This part of the house is double brick and has no wall insulation but it looks like it is too expensive to retrofit it. I did hear on the radio this morning that sealing up the ventilation vents on the top of the walls helps to keep the house warm in winter.
Sub floor insulation
(13 posts) (8 voices)-
Posted Saturday 15 Aug 2015 @ 6:58:29 am from IP #
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johnmath
Member -
Oilburner
MemberThings cool off at night as the temp drops. If Insulation keeps the house warmer in winter, it's not going to know the difference in summer and keep doing the same thing.
Cold does not travel upwards either so if insulating the floor will make the house warmer in winter, it's going to retain the unwanted heat in summer.
I have a DIY cooling system under the house.
I have an area that is surrounded by shade cloth. Around the top of this is some irrigation hosing which sprays a very fine water mist onto the mesh. In the centre of the mesh area there is a hole in the floor which is in a corner of a room and was the result of some patched flooring when we got here. Under the hole is an Inline ventilation fan secured underneath it. The fan sucks the MUCH cooler air from under the house and pushes it up and into the 2nd Loungeroom which is in the middle of the place.This simple system is amazingly effective and also has the benefit of providing some pressurisation of the internal air which means hot air is more likely to be pushed away when doors are opened. There is a power point on the wall inside right near the hole where I plug in the ventilator and the pump to run the setup.
I have used this setup for about 10 years now and it works great. Was cheap to set up and uses very minimal power. The difference it can make to the house is amazing.
Posted Saturday 15 Aug 2015 @ 5:23:07 pm from IP # -
Morbo
Membertemperatures are more stable underneath the house and subfloor insulation makes maximum 4 degrees difference. In summer less heat gets in at daytime and there should be windows you can open at night.
When you put the heater on, the subfloor insulation keeps a bit more heat in. I think it mort about the radiation side of things and also there is a still air pocket created. I am measuring since 5 years now. And batts or foil or styrofoam, there is next to no difference.Posted Saturday 15 Aug 2015 @ 10:31:00 pm from IP # -
I'm confused. Does underfloor insulation help keep the house cool in summer, or does it retain unwanted heat as Oilburner says? Johnmath could you expand please? In summer after a few 30c days in Sydney our house stays hot no matter how many windows open or fans on. In winter it's usually about 3-4 degrees colder inside than outside. You can feel the chill when you walk in.
Oilburner, how big an area are you talking about? I don't think we have the space for a cooling system.Posted Sunday 16 Aug 2015 @ 8:10:53 am from IP # -
Oilburner
MemberLenarufus said:
Oilburner, how big an area are you talking about? I don't think we have the space for a cooling system.Surprisingly small I think, About 1m Sq. I use those micro mist Nozzles for the garden watering systems. I could increase the size of the meshed off area or even do a double mesh but then there is the water trade off. Currently I use IBC tanks which do seem to keep up pretty well a good summer storm can fill and over flow them easily.
This summer I am going to try using the pool water pumped through a radiator that I have put in to use with the veg oil heating system. I'll just pull water from the bottom of the pool, pump it through a radiator with fans on it and cool the air coming into the house.
Never known the pool to get as hot as the ambient temp so there should be a few degrees of relief there and a car radiator has a huge heat transfer capability compared to the output of an AC. The temp Difference wont be near that of what comes out of an AC but the Volume of the cooler air can be massively higher in compensation.You are dead right in your description of how homes stay hot in summer and cold in winter. I live in sydney too and know exactly what you mean. Once the heat gets in, you are dealing with a hell of a thermal mass to get it cool again.
Another thing I do in summer is have a car radiator fan on the side of the house that doesn't get much sun. On those really hot days and especially nights, I have this sitting in a window and run it off a battery charger. It helps push the hot air out and pull the now cooler air in. Even with the huge CFM that thing does, the house still radiates a lot of heat inside.
The fans, underneath and in the window would be capable of easily doing a full air change on the place in not more than 10 min but still even running the things for hours, the place can still be hugely warmer than outside. I was thinking of getting a solar controller Module from fleabay. I would use this as an automatic sensor. I could program a temp and once the house got hotter than the outside air, the thing would kick in. It would also work in winter when the outside was warmer than the inside temp just by switching the temp parameters around.
Like you, I sometimes wonder about the over all value of insulation. People talk about not letting the heat in but that is rubbish. You can't seal and insulate a house as well as a fridge but even a fridge will quickly warm up when switched off.
It seems the ideal type of insulation would be one you could switch on to work say on a cold day to keep the heat in then switch it off during a the evening of a hot day to let the place cool off.Posted Sunday 16 Aug 2015 @ 8:52:21 am from IP # -
JamesRowden
MemberI got my ventilation done from the experts. The system installed helps keeping the winters warm and summers cool. The sub floor insulation helps you get the system done. Ventis home ventilation may help you with the solution.
Posted Tuesday 13 Oct 2015 @ 6:41:00 am from IP # -
I was about to say solar air heating will bring in solar energy in winter when your home is cold and in summer it will expel the hot air and allow cooler outside air to enter. you can heat the air in your house first then start heating the underfloor area for some heat storage to use after the sun goes down. How long this will last depends on your home insulation. the more insulation the longer the house will remain warm. Having underfloor space is a bonus for this type of heating, as you use the underfloor materials to store energy for later use. I have patented and now manufacture such a system here in Armidale NSW where it is cold. I cant put my website up as it is not allowed but if anyone is interested in contacting me I will pass on the information. I think that is allowed . I have had the heater tested by a professor from the New England University and it is 90.5% efficient. It is without doubt the most efficient Glazed solar Heater in the world. The test report is published in the website.
Posted Tuesday 13 Oct 2015 @ 11:36:03 am from IP # -
con said:
I was about to say solar air heating will bring in solar energy in winter when your home is cold and in summer it will expel the hot air and allow cooler outside air to enter. you can heat the air in your house first then start heating the underfloor area for some heat storage to use after the sun goes down. How long this will last depends on your home insulation. the more insulation the longer the house will remain warm. Having underfloor space is a bonus for this type of heating, as you use the underfloor materials to store energy for later use. I have patented and now manufacture such a system here in Armidale NSW where it is cold. I cant put my website up as it is not allowed but if anyone is interested in contacting me I will pass on the information. I think that is allowed . I have had the heater tested by a professor from the New England University and it is 90.5% efficient. It is without doubt the most efficient Glazed solar Heater in the world. The test report is published in the website.Posted Tuesday 13 Oct 2015 @ 12:17:48 pm from IP # -
JamesRowden said:
I got my ventilation done from the experts. The system installed helps keeping the winters warm and summers cool. The sub floor insulation helps you get the system done. Ventis home ventilation may help you with the solution.As far as I am aware Ventis closed their doors in January.Phones were down, emails rebuked. Recently their facebook page came down. However there was a mention that the name was taken over by a new company - no public mention.http://www.smartcompany.com.au/finance/49485-former-smart50-finalist-ventis-hq-collapses-into-voluntary-administration/
Posted Wednesday 27 Jul 2016 @ 12:58:21 pm from IP #
