Winter sun, first snow...

It was a chilly, raw weekend, and we certainly felt it in the caravan! I just couldn't get my feet warm the whole weekend, so on Sunday afternoon took a stroll around the fields to capture progress 'from a distance' on ECF2 after so much time focussing on the nitty gritty detail.

Heat Pump: Part 2 - ground loop installed!

Roof progress & problems

Since last week when I mentioned that it hadn't rained much it has of course chucked it down most days this week! Ironically we had no water for most of yesterday as there was a burst water main somewhere on the west side of Loch Lomond which is a good distance from here.
Even the joiners finished early yesterday as they were soaked to the skin but this was also around the time that Steve and I realised/believed that some of the roof windows were not in the positions we had expected/designed. We arranged for the architect to visit site this morning....

Up on the Roof

Since last week's blog progress has been slow but steady. The roof is quite involved and various references have been made back to the timber frame manufacturer and the strucural engineer during the course of the week. To an extent it appears to be over-engineered (but I'm only a surveyor!) We employed a structural engineer to undertake much of the design as this was meant to save time with the timber frame manufacturer; I'm not sure this has been achieved and certainly the cost seems to be a good chunk higher. If we did this again we would handle this aspect differently but 'it is what it is'. The gloom of some dreich November days don't help and I'm beginning to hate the small cold caravan bathroom!!

Heat Pump: Part 1 - ground loop

Turning Chillier part two

A continuation of the previous blog - the technology sometimes prevents such things. The step shown left was finished on Friday. The stone for the whole wall and the step has been recovered from the demolished farmhouse save for the coping stones which have been bought from a nearby farm where the wall had fallen down. The weather forecast for later in the week is distinctly cooler with daytime temps nearer zero and we have had our first conversations around the subject of 'how long can we/will we stay in the caravan'. No decisions to move out yet as most of the time its really not difficult. Naturally we would prefer more space and a lovely big bathroom but that is, quite literally, a work in progress. The office is in an old toolhouse adjacent to the barn which adjoins the house and with its high level of insulation it is a very pleasant place. Steve has been insulating the water pipes within the caravan and we need to tackle the ones outside where they are not underground.

Turning Chillier

As Steve's previous blog mentions the first floor is in place and in response to Jane's query on keeping the water out you can see the blue sheeting which is keeping the worst of the rain out. Even so I don't think we're getting as much rain as usual for this time of year .....famous last words?!

By close of play last Friday - 2hrs after this photo was taken - the ridge beam and both gable walls were complete. During the couple of days prior to this, by quirk of structural engineering design the first floor boarding was glued and nailed in place, the idea being to provide a strong joint between the 1st floor I-beam joists and the binder plate (a deep beam which runs along the top of the ground floor wall panels against which the ends of the joists are butted).
In my (and our joiner's!) view this was quite an unusual detail, but a call to our stuctural engineer - "just to make sure..." - clarified the thinking behind it. The downside was that the T&G chipboard flooring had to be protected from the weather until the building is made watertight, as being merely 'moisture resistant' isn't exactly a qualification for survivablity for up to a month's battering by the west of Scotland's climate in November!This coming week should see the completon of the 1st floor wall panels and start of work on the roof. On the 'goods inwards' front, the windows are due to be delivered this week and possibly the Pavatherm wood fibre insulating cladding board.

Ridge beams...

Dry stone dyke

Portal frame arrives

Late afternoon yesterday saw the arrival of the prefabricated portal frames along with the brackets and bits to put them together. These are more than a week overdue and their late arrival has meant a temporary stop on site for a few days as nothing further could be done without them beyond the ground floor panels which are now in place .
However, things moved along again today as our main builder/project manager and two joiners started to the erect this steel framework into the gound floor panels. By the end of the day two of the three frames were in place and secured.
So why a portal frame? Well, this 1.5 storey house is very open plan internally with generous internal room heights (2.7m ground floor, 3.5m kitchen/diner, 2.9m first floor) such that the upper floor ceilings follow the roof line almost to the ridge, with a small loft space around 1.5m high. With this internal design it was tricky to use a (more conventional) truss system, so the portal frame is used to provide torsional stiffness to the building and carry a roof ridge beam, against which rafters will be supported for the roof. In effect, this is a contemporary take on a traditional method of roof construction.
In designing the roof we have also avoided the use of roof purlins (horizontal rafter supports) by using timber 'I-beams', each of which will span around 5m from eaves to ridge at a 45 deg. pitch and carry the weight of the slate roof supported only at either end. This not only keeps the internal structure clean and uncluttered, but their 352mm depth will be fully filled with insulation and their thin shear web minimises thermal bridging. The end result is a stiff, clean, super-insulated roof structure.
The down side to this constrcution has been additional labour/time and ultimately cost, but the end result should be worthwhile.

Daily Changes

The two joiners erected much of the ground floor on Monday and Tuesday which has been really exciting. Its terrific to see the rooms take shape and we are really pleased with the size of the window openings, particularly as we spent a long time last winter working through that element of the design. The joiners can't progress further until the steel arrives, this is delayed but due next Wednesday. In the meantime the scaffolders have been taking delivery of their kit and today have erected scaffolding on the west and south elevations. This photo is taken through the caravan window.

By and large we've had good weather since the start of the build, it is very mild at present which makes life comfortable for early mornings in the caravan.....however the past 2 days weather have included a large amount of rain and the area at the back of the house is somewhat muddy. Thankfully the caravans are on a concreted area.

Exciting Progress On Site

One of the landmark days on site - the joiners arrived at 7.50am, the first lorry and trailer load of timber frame a few minutes later. The first photo was taken around 9am as the timber was being moved to the house; the joiners spent much of the morning undertaking check measurements etc (apparently it was all within 5mm so that was good!) and moving the timber to the right place.

We had some wild Autumn weather at the weekend so it was a chilly post-frontal breeze as well as getting muddier around the site.

True low carbon or eco-chic?

Probably since the oil crisis of the early 70's there has never been such a high level of public awareness and engagement in all things 'environmental', not least in greening up homes. In particular the UK Government has made a commitment for all new homes to be 'zero carbon' by 2016, an ambitous target which would make UK building regs on energy efficiency some of the toughest in the world, even exceeding the current high standards which exist in Canada, Scandinavia and Germany.

Future Plans

This week we've instructed the architect to commence work on plans for the former dairy. We're looking into the possibility of converting the building into holiday accommodation and prepared a brief to that end. We are very fortunate to live in a beautiful part of the world and the National Park designation has further enhanced this area's popularity for visitors. As you can see the slate roof is hanging together but there are some nice features to the building and we would like to bring it back into good use. The building is to the north of where our house will sit. The brief still adheres to our low energy principles but with an exisiting shell the approach will be different. At this stage we are looking at what sort of space we can create within the structure as it stands and exploring the planning situation.

Timber Frame Disappointment

Today the forklift was dropped off in order to be ready for Monday when the timber frame is due for delivery. Three year old son just said 'wow' and is very excited that more machinery is on site. Unfortunately a couple of phone calls and a visit from the builder brings news that certain elements of the kit are not ready - namely the steel portal frame and the first floor TGI joists. This means that work can start on erecting the timber frame next week but the extent will be limited because the steel portal is to be integrated within some of the prefabricated wall panels on site. This is disappointing for us but is outwith our control or influence so not worth stewing about. For the builder it is perhaps more frustrating, particularly as there has already been a break of three weeks of fairly good weather since significant work on site and as he has lined up scaffolding and crew to go full steam ahead on the frame.

Wall plates installed

On Tuesday of this week the builders spent the morning fitting the wall plates (also called 'sole plates'). In timber frame construction these set out the plan of the ground floor layout and form the interface between the walls (both external and internal) and the ground floor slab/foundations.
The wall plates comprise timber of the same width dimension of the wall panels they support (ie. 140mm and 89mm), and are simply cut to length and laid on a bed of mortar (and damp proof course at the outside walls).
Whilst an apparently straightforward process, locating the wall plates in the correct positions is critical to the ultimate accuracy of the frame installation.
As an aside, this process also introduced a simple but effective airtightness detail to the building, in that the overhanging damp proof membrane (from under the slab) is folded back over the slab at the edges for later trimming and connection to the vapour membrane to be installed on the inside of the wall panels. Whilst not an essential detail (and usually omitted), this ensures an airtight and flexible linear floor/wall joint that should last through the first few years of the building 'settling' and drying out, a process often responsible for significant degradation of airtighness as cracks open between differing materials (eg wood/mortar) and thus worsening energy efficiency. Polythene membrane, being a flexible material, withstands this movement.
As an aside, airtightness is a key component to low energy building design alongside insulation, the minimisation of thermal bridges, orientation and glazing. Coupled with this it is essential to have an effective ventilation system to ensure good air quality inside - more on this and other airtighness details as the house takes shape.

Four Months of Caravan Living

We've been living in the caravan for just over 4 months now, its hard to believe and generally has worked a lot better and been much easier than we expected (all those years of camping provides good training!). Yesterday was a horribly cold damp foggy day though and I felt chilled to the bone. By the evening I just couldn't get warm and the prospect of a warm bathroom in a real house would have been lovely. Its a better morning outside today but the water heater won't work and after attempts to remedy the problem we've called the engineer who is coming out this afternoon thankfully. If it doesn't work I'll be 'phoning a friend'.

All quiet on site...

It's now two weeks since the floor slab was poured with most of the ground floor plumbing and underfloor heating pipes in-situ. The planning and preparation work appears to have paid off as overnight rain reveals little ponding of water indicating we have a flat and level slab within the specified tolerance. All services are also now in place within the slab, having been 'introduced' to the inside of the building via pipework and ducts, with just the soil pipes to be revealed by tapping away the few mm of concrete over their sealing caps. Little has happened since on site with the exception of the delivery of the timber frame sole plate material to be fitted in readiness for the main house frame, this being schduled for delivery w/c 29th October, although there has been much 'to-ing' and 'fro-ing' between frame supplier, builder, architect and client (us!) over minor changes to dimensions of components and materials. In the meantime, we've put some more effort into landscaping works and have started to plant up behind the drystone faced retaining wall, this being almost complete bar coping stones (proving quite hard to come by!).