Grand Designs building received ground source heat from CTC

You may recognise them from the TV programme Grand Designs. It showcased their mind-expanding creation. The different floors are slightly curved to maximise the view of the sea. The first floor, in cast-in-place solid concrete, in one direction and the second floor, entirely in cross-laminated wood, in another.

There is also a third floor that is all glass.

- It feels surreal that we did this. You have to pinch yourself," says Petra Ellström about how, after years of thinking, they finally made a move and built their dream house in a hard-to-reach location.

- It's awesome. It's like a spectacle with the fairway outside, different shades of colour and changing weather," says Jakob Paulin.

Left the big city

The house is located north of Stockholm, near Åkersberga. Outside the window, the ferries between Finland and Sweden pass by. Jakob Paulin, 52, works as a mechanical engineer and designer, Petra Ellström, 51, is a computer engineer. They have two dogs.

When they found the place fourteen years ago, they were real city people. Living in an apartment near Odenplan in Stockholm, it was busy, noisy and convenient with shops open at night. Then they bought a summer house in the country. Quiet, far from the shops, quiet.

- We liked it here very much and moved here permanently a few years later. Then we had a look at the hilltop above our house and thought it would be cool to build something there," they say.

Choose ground source heating

Their three floors are heated by geothermal energy, a CTC GSi 616. 1300 metres of underfloor heating hose were used to heat their 300 square metres of floor. The couple are delighted, the two borehole pump is running nowhere near its maximum capacity despite a lot of floor space, large glazed areas and a windswept site.

- I've always wanted geothermal heating, we've known for a long time that it's convenient and a good investment. In addition, we live on a mountain, so it feels natural that we invested in it, says Jakob Paulin.

They have solar cells on the house and the idea is that they will provide the electricity for the geothermal heat pump. That way they will be self-sufficient in heating.

- We are very happy. We adjusted the settings in the beginning, but then it just kept on going. We don't have to do anything.

Sustainable thinking

For Jakob and Petra, it has been important to think about economy and the use of resources in the construction process. Everything should be robust and of high quality, not a waste of time. Having a geothermal heat pump is a long-term investment.

- We chose to invest in a large and solid house. There's a lot of concrete, so it feels safe to be here on the hill even if it's stormy. All things, including the heating, should last a long time and require minimal maintenance. It should be things that are durable," says the couple.

So while the house may be a little crazy, worthy of a movie villain of the worst caliber, we at CTC think their philosophy seems sound. They believe in quality and durability.

Facts:

• Petra Ellström and Jakob Paulin have a spectacular house north of Stockholm, near Åkersberga.
• Both are interested in technology and engineering. Building a house on a hill where it slopes 45 degrees to the road was a challenge they relished.
• The house has three floors that are twisted in relation to each other. One is concrete, the second is wood, the third is glass. On the roof is a helicopter pad.
• They heat the house with geothermal energy, a CTC GSi 616. They have drilled two holes in the rock to have enough capacity to heat almost 300 square metres of floor. There is underfloor heating on all floors.
• The construction of the house has been portrayed in TV4's Grand Designs series and can be followed on the couple's Instagram account Villa Alsvik.