We thought long and hard about what to use for this, and eventually decided to go for sheeps wool insulation. It needs to be about half as thick again as conventional insulation such as Cellotex, costs about 15-20% more, so about £200 plus VAT in our case.

The web site of the people we bought it from, www.blackmountaininsulation.com/ pretty much convinced us that it had so many advantages over conventional materials the small extra cost was irrelevant. It is treated with Borax to protect it against moths and insects and this also gives it greater fire retardance, but has no other chemicals in it, and “breathes” as well as insulating, so avoids the risk of moisture becoming trapped and creating mould.

 Here is the sheeps wool arriving in the lorry! It’s very light and easy to handle, in fact quite fun to through around!

 The cold return pipework on the comfort cooling system needs to be insulated. So conventional plastic 125mm diameter pipework gets  a sleeve made of thin bubblewrap with metal outer skin slipped over it. Joints are taped with the self adhesive metal tape used for a variety of ducting work on houses.

Here you can see one pipe coming into the ceiling of a bedroom, and another pipe on it’s way down to the lounge. This pipe will be hidden in a “fitted cupboard” as will the warm air pick up from the lounge which is at the other end of the cupboard.

You can also see the white overflow pipe which goes up to the chiller to allow any condensation in the chiller to be removed. This has a small trap (u bend) under the chiller. 

 Sitting between the 400mm stuc centres is the 2″ vacuum pipe, here fitted with a branch and a wall socket back box. It’s similar to putting in an electrical wall socket and indeed the vacuum socket is set at the same height for ease of use and asthetics.

 We’ve been intending to fit this since the early house designs were drawn up. We saw it in a friends self build in Cornwall and could see the advantages. A 5 metre length of hose is all you need to carry around when cleaning the house. 5 or 6 “sockets” enable you to plug the hose into the sockets, which are linked via piping through the house to this unit which will live in the utility room. Pushing the hose in the socket automatically switches the unit on and it vents it’s exhaust to the outside of the house. We will be having engineered floors throughout most of the house with the exception of the tiled “wet” areas and a duct that fits into the plinth of the kitchen units will be ideal to just brush the floor, touch the duct and the dust is sucked away, without even getting the flexible hose out.

 We’ve used some engineering bricks to build up around the “conning tower” of the rainwater harvesting tank to fix the cover supplied with the tank in place and at the correct finished level. We can now backfill with dig and then top soil to landscape it off. With the potential for people to fall into the tank (the water in it can be about 3 feet deep or more) a secure cover is essential.

 To improve heat and sound insulation we are using Rockwool R40 between the joist spaces. Not as nice to work with as the sheepswool insulation we are using for the roof insulation which is also being done and we will cover next week.

 Whilst the errection of the external log walls is pretty straight forward, the internal marriage of the stud work walls to the log walls is poorly detailed by the log house suppliers. Where we have decided to use log “siding” (2″ thick slices of log which look like a full 8″ log but are fixed like monster sized “tongue and groove” to the stud framework) in order to get a good seal between adjoining rooms we are cutting a 2″ slot so that the siding does not leave a cheek shaped hole between each log. The devil as they say is in the detail.

 We are at that stage of the house where to the untrained eye nothing seems to be happening, but the house is being stuffed with wires, pipes and things to make the house “work”. Here is the foul waste pipe coming down from the upstairs bathroom, various electrical cables and mains feeds to the bathroom sinks etc. The plumbing is further complicated by the “grey water” system for the toilet flushing which will come from a header tank that the system’s pump will fill up. Once all these services are in place we can start fitting the ceilings and wall finishes. This will be a mixture of log siding on some of the internal stud walls, plasterboard on others, generally plasterboard on the ceilings but some tongue and groove in a few places too.

 It seems like a long time ago we were using a monster drill to create conduit routes for wiring in the log walls. Now it’s time to find all those routes and chop out recesses for sockets for light switches and 13amp sockets, pull the cable and leave it ready for the “second fix” when they will be fitted.

 There was just enough space in the eaves to fit the heat recovery and the comfort cooling units. The comfort cooling unit on the right re-cycles air in the room, passes it over a heat exchange matrix which uses the cold return feed from the heat pump to reduce the air temperature by about 7 degrees. So the return side of this has to be insulated (the sliver stuff). The heat recovery pipes only have to be insulated where it goes into “cold” spaces such between the rafters above the sheepswool insulation.