Energy Saving


We have a log stove which is mainly used at weekends. Our logs mainly come from what we collected when we had a 2 month 'gleaner's licence' from the forestry commission. You are allowed to pick up anything you can carry once they have finished with an area. We also have some of our own now from the trunks of a large Leylandi hedge cut down to enable the wind turbine to work without obstruction. We replaced the open fire with a wood stove which is 80% efficient rather than 20% for the open fire.
We replaced our aging Oil Boiler with a Ground Source Heat Pump which produces the majority of our heat. These systems work best in well insulated houses as they heat the house all day long with a small set back at night. 


Cavity Wall

We have had Cavity wall insulation installed. There are grants which mean we paid £199 for an area the size of an average home then commercial rate for the difference. If you are elderly or on low income you should get it free. Contact Changeworks for advice.

Loft Insulation

We have gradually installed additional loft insulation using thermafleece made from sheep's wool and additional rockwool. We could have got a similar grant if we'd wanted to do it all at once, but got it cheaply as there were special offers at the DIY stores. We are now up to the recommended 270mm throughout including the top layer over the joists. The joists were providing a cold bridge and the top layer has made a surprising difference.

Draught Proofing

Our house was very well ventilated when we got it, however the wind blew underneath the house through the many vents in the wall and through the roof space through the many vents in the roof and through the wall cavity between the two, this meant that when the wind blew it could get quite cold, so we blocked some of the vents up to reduce the wind blowing under the house and cavity wall insulation stopped the wind blowing through the walls and we blocked some of the vents in the attic which reduced the flow of air through that as well.

Under Floor Insulation

The space under the floor is well ventilated. There is only an 18 inch gap at best. The current building regulations specify 100mm of this or 150mm rockwool/ sheep's wool but it was not required when the house was built. About 15% of heat is lost through the floor. After much deliberation we managed to get a joiner to try to install insulation in the back third of the house which is north of the rest and therefore coldest. It also has the most gap under the floor, although 18 inches is probably generous. He gallantly tried to squeeze in under the floor, but neither he nor his assistant could manage it. I however, being only 5'4" and though middle-aged, still in reasonable shape, could! We started with him cutting Kingspan slabs to size and handing them down. However the gaps between joists varied considerably and it was not easy to do precise measurements under the floor, so we made slow progress, only completing a room in a day. I then suggested sheep's wool. This has the advantage of being  flexible so easily dragged under the floor and fitted to the variable width of the joists and not having any fibres to deal with as with rockwool. It is quite a bit more expensive though.
 The next problem was how to hold it up. We thought about a net, but this would have been very difficult to get under the floor and secure. We then came up with scrap wood batons cut an inch or two larger than the gap and wedged between them by hand. We eventually came up with 2 sizes as there are occasional extra large gaps but if they are too big they don't wedge well. The joiner cut hatches to enable access to each section of the area, supplied me with batons and left. (We discovered that there were already hatches for each radiator). Although the sheep's wool is nice to work with, the space is very dusty, so I have needed old clothes, (preferably an old 'hoody' to protect hair) a mask and swimming goggles have been better at staying on than normal eye protection, although they sometimes do get a bit steamed up. I hope nobody comes to the door while I'm at it! Its better to have another member of the family above ground to feed it down although they have the habit of getting bored and wandering off!
The rooms now completed need very little heating. The Kingspan room, although up to current regulations with 100mm thickness whereas the 100mm sheepswool is  less than current building regulations, has suffered from condensation.

Vents above windows

Our fairly poor double glazing has metal vents above most windows. Even when closed, these provide a cold bridge. Particularly in very cold weather, over night condensation was literally dripping off them onto the window. We unscrewed these and filled with a small amount of sheep's wool, which should still enable them to be used for ventilation in the summer. This led to a dramatic improvement on the amount of condensation.

Condensation is mainly caused when warm moist air cools and then cannot hold its moisture. It will tend to condense on the coldest surface, usually windows but also poorly insulated doors. If you have such a leaky house that condensation escapes anyway there is less of a problem though obviously you are wasting a huge amount of energy. Turning heating off at night or when you're out obviously saves heating but risks causing condensation. We have managed to tackle condensation in a number of ways;
Reducing steam from cooking by using lids and microwaving rather than boiling, including for coffee.
Increasing the insulation generally in the house reduces the amount that the house cools down over night and therefore there is less moisture needing to condense. We have replaced rockwool above the rooms most prone to condenstion with sheep's wool and used the rockwool to top up elsewhere. Sheep's wool naturally absorbs moisture and actually becomes more insulating when it does so, but is more expensive, so we have used it strategically. Sheep's wool is used for most of the underfloor insulation and rooms done with this seem less prone to condensation.

Heat Recovery Fans
Subpages (1): Heat recovery fans