The Wooden Frame

Our friend Marian has now been employed as our building contractor and his team of carpenters, led by Rudolf, are putting together the wooden frame of the house. They started at the beginning of June and these photos were taken on 16 June. Everything is happening really quickly now, and the skeletal frame should be ready to mount on the foundations on 21/22 June.

We will then be able to get an official valuation of the house (the walls will be more than one metre high!), transfer our flat mortgage to the house, and sell our flat to raise the cash for the next stages. We have found buyers for the flat who (if they don't pull out!) have agreed to pay straight away and let us stay in the flat until the end of September, so the house will have to be ready by then!

By the way, we have now come back round to the idea of having a heat pump to provide heat and hot water, and not solar panels! The heat pump can be connected to the 'Sole Kollektor' and the 'Sole-Luft Wärmetauscher' (official English translation welcome!). 270m of 3cm-wide tubes have already been installed 2.5, 1.8 and 1.1m deep in an 80cm-wide and 45m-long trench under the garden. An anti-freeze fluid will run through these tubes. We went a bit overboard, as 160m would have been enough, but we can always choose to connect up only two of the 90m long tubes. Bjorn is negotiating a good deal on the heat pump with an Austrian company, as our house will be the 'pilot project' in Slovakia.

Check out: http://en.wikipedia.org/wiki/Geothermal_heat_pump for more info

The first walls of our house and Adam in the workshop.
Alex the carpenter says, "Mummy, how long did you say I had to finish this jigsaw puzzle?"



The pieces of wood with the gaps and mesh have come from Germany and the rest from Slovakia.

Various pieces of the frame ready to be put together.

Adam and Alex carry out a quality control. Cellulose (recycled newspaper) 360mm thick will be blown into the walls during the final stage to provide insullation.

Alex looking through the windows.

Foundations Finished - March 2007

We've had a bit of a break in postings due to technical reasons, as our home computer crashed with lots of photos on it and we haven't been able to recover the hard drive yet. Emma has also started a new job and has been very busy. Anyway, the foundations were finished in March 2007 and these photos were taken in April 2007. The West garden and base for SW terrace with pebbles. 270m of 3cm-wide tubes for the heating system have already been installed 2.5, 1.8 and 1.1m deep in an 80cm-wide and 45m-long trench under the garden.

The back garden and base for terrace with pebbles.

Most of the foundations with Adam, Emma and Alex and vineyards in the background. There is a good echo down the pipe!

Front garden, path and shed with detail of wall foundations.

The East garden and SE terrace (pebbled area). The mound of earth is where the carport will be and is being saved to make the clay 'plaster'. In front of it are the foundations for the main shed.

The East fence and garden from another angle. A cycle path runs under the row of trees in the background.

Finally, the photos you have all been waiting for!

The land in January after it had been cleared of the vines, trees and bushes. The path on the right is the access road to the house behind our plot.

17th February 2007: Alex the builder, and other builders, laying the concrete bricks of the foundations. We are trying to do our bit to stop global warming by building a passive house, and global warming is helping us by providing the warmest winter on record.

The king of the castle!

View of the street.

19th February 2007: Visited site with Mum (Hazel). The concrete has been poured into the foundation walls.

3rd March 2007: The main concrete slab has been poured.The rectangles on the left and at the back are for the outside storage areas/work room. The left side from back to front will be the kitchen, hall, downstairs bathroom and kitchenette of guest room, the middle will be the dining room, stairs and guest room, and the other half of the middle and the right-hand side, including the jutting out bit, will be the living room.

Other news

Following discussions with Bjorn, and based on the results of his research, we are going to go for solar panels and an electric boiler to provide our hot water needs. The heat pump option would be more expensive and complicated.

Following negotiations with the bank, we are going to use the route below to finance the rest of the house:
a. borrow a lump sum immediately using Maria’s (Peter’s Mum’s) flat as collateral (she agrees!)
b. invest this money into the house, and then get a valuation done. Our current mortgage on our flat will then be switched to the (unfinished) house (this will ensure that we continue to receive the state benefit each month)
c. sell the flat and invest the proceeds in the house
d. get another mortgage on the house to cover any extra costs

Foundations Started

On Wednesday we signed the contract with the builder who is doing the ground works. Holes for the foundations have been dug this week and the concrete may be being poured as I write. They are also putting in the pipes for the heat recovery / ventilation system. We are going to take some photos tomorrow. If the weather stays mild and dry all the ground works should be finished in two to three weeks’ time.

We are now trying to work out how we are going to finance the next stages. We should order the wooden construction and windows as soon as possible (and we need down payments for these). Once we have ordered them they will take six to eight weeks to arrive. Then the house can be built within a few weeks! In order to get a mortgage though, the walls need to be built to 1m above ground level. As our house is being pre-manufactured offsite, this is not going to be easy. We might have to persuade the land registry office (which will value the house with its “1m high walls”) that this criterion does not apply in our case. Peter has an investment fund that he may be able to borrow from, or we might have to sell the flat we are living in and rent a place for a few months if we just can’t get a mortgage at this stage!

Here are the contents of some recent e-mails from Bjorn. We will be discussing all the options and hopefully making some decisions on Sunday.

Some explanation as to the Zemný Výmeník (SOLE collector). Planned were 165 running meters of tube for pre-heating (winter) or cooling (summer) the air. I added another 100rm (it will be close to 300rm) to make it more effective, both winter and summer. In fact it is now long enough so that you theoretically could connect it to a heat pump (tepelné čerpadlo) up to 5KW. I made a calculation - such a heat pump would cost around 220 000.- including installation. But it would not be very reasonable to do so, because of the temperature gradient being too big (from about 1° to 55° for heating and warm water) the power ration (výkonové číslo) is only 3,2. (For 1KW el. you get 3,2 KW heat).

I now propose a different solution: Longer SOLE collector to boost passive gains (Winter and Summer) + larger solar panels (5 panels instead of 2) with cca. 10m2 + and direkt heating with electricity for the rest (el. spiral in solar heat tank). No pellet oven. Extra cost: 45 000 SOLE, 80 000 Solar. Saved money: 300 000 pellet oven + installation and exhaust pipe. The Solar panels will cover your need for hot water to about 68% and passive gains from the SOLE collector and especially solar collector will cover about 1/4 of your heating demand.

I calculated the need for electricity for 1 year for your house. You will need 1300KWh to heat hot running water during winter time, and about 2000 KWh to heat your house. All in all this is 3300 KWh per year for heating. Compared to that you need about another 4000KWh for all your other appliances (light, washing, cooking etc.). The price for you is 1,87 per KWh if you heat the house + 400 per month (tarif D11 from ZSE, 20hours a day, peak is more expensive, but you will not use that for heating). Because your heat losses are so small, heating directly with electricity makes sense.

Soon it will be possible to buy wind powered electricity (in Germany you can do that already) and it is probable that in 10 years time it will be feasible to mount photovoltaics for a reasonable price that will produce 3300KWh/a or more on your roof - this makes only sense if that gained electricity can be sold directly into the grid. This is possible in Germany and Austria today. This seems to me a sounder ecological strategy.

The pellet oven could save you the 3300KWh in electricity - but the price of the pellets would be comparable to the price of the electricity - and for the 4000KWh you need for other appliances you would get a higher tariff so effectively you would pay more. Failure of electricity: any power loss up to 24 hours will not change the inside temperature by more than 1°C.

There are small free standing ovens that burn bioethanol and produce only water vapor and CO2. These can be used for extra heating (up to 2KW) in passive houses. Bioethanol is expensive though, and is only meant for a once in a time use. These ovens are new and cost about 80000 SKK. I don´t think that would be necessary, I mention this only to inform you about possible back ups.

One more possibility:The heat pump is only slightly more expensive than the solar panels. So if we would skip the solar panels completely, we could replace them with the heat pump. With an overall need for heat of 7000KWh/a we would probably only need 2200KWh electricity, even less than with solar panels....life expectancy of a heat pump is a bit lower than solar panels, but the system is more compact and easier to install.

Finally, here is another website that is good if any of you in the UK want to make ecological changes to your homes: http://www.est.org.uk/ And it explains some of the things mentioned above.

The Story So Far

Intro
This blog is going to record the building of our passive house near Bratislava, Slovakia. We have a bit of catching up to do, as work has already started.

The concept
We aim to build a passive house. It will be super energy efficient, with thick, air-tight walls and a heat recovery ventilation/heating system. It will not have any conventional central heating. We aim to have solar panels to heat water, which will be backed up by an electric boiler. The windows will be triple glazed and mainly south facing in order to catch the warmth of the sun. Shutters and the ventilation system will keep the house cool in the summer. We will provide links to websites and more information on these things in future posts.

Plot
We bought our plot of 550 square metres plus 50 metres of road in March 2005. It is next to overgrown vineyards and a field path leading up to the hills and down to the village. A walking/bike path goes from the bottom of the road up into the hills where it links up with a cross country skiing "loipe" and other walking paths.

Road and utilities
A local developer has built the road and connections to utilities. Work started on these in Summer 2005 and the last part of the road was finished in November 2006.

Architects
Our architects are Bjorn (Norwegian) and Zuzana (Slovak) Kierulf. They own the company Createrra.

Plans
Bjorn and Zuzana worked on the plans for several months. They finalised the outline drawings in December 2005, and the detailed plans were submitted to the planning authorities (town council - "Mestsky Urad") in July 2006. Various experts (water engineer, electrician, structual engineer, ventilation expert, fire inspector) also added their parts to the plans.

Planning permission
We had outline planning permission to build a house when we bought the plot. Final planning permission was given in November 2006. It is relatively easy to get planning permission for new houses on new estates in Slovakia. Any style of architecture seems to be acceptable, and every house can be different.

Ground works
Bjorn has found a builder (Pavol Kotul) to do the ground works. His team cleared the land of the old vines and tree just before Christmas 2006. Work is now starting on the foundations and the laying of the underground pipes for the heat recovery ventilation.

Photos and more details will follow soon. Here are some links for now:
http://en.wikipedia.org/wiki/Heat_recovery_ventilation
http://www.europeanpassivehouses.org/