Know what to expect
Planning a house involves many many choices. Some of those have more and some of them have less impact on the budget. The difference is not always obvious, so we inform you right from the start what effects your decisions will have on the total cost.
In general terms, Ecoframe house costs are slightly higher than the same size factory-made houses. This can be as little as 10% more, or even 40% depending on the choices you make. The unit that is used is euros per square meter, and a basic ecological factory house maybe around 2000, including everything from the foundation up. Unfortunately, sometimes people quote lower, incomplete, prices to hook people in, so be careful if you hear anything substantially lower.
The main cost factors we will discuss
We will try and put some rough estimates to it, but ultimately we have to calculate for your specific house.
Going with the price per square meter model that we mentioned above, a basic Ecoframe house is about 2200. The extra is mostly due to the passive house insulation, the ecological materials, and a little because of the frame (see below).
The key thing to achieve during design is the maximum size that fits your budget and gives you the number of rooms you require. In other words, the size is not the main question, but the number of rooms. This is where the upstairs of a 1 1/2 storey comes in.
The basic timber-frame (without trusses) is always part of an ecoframe house. Its cost is partially amortised by the lightweight materials used in the walls.
In other words timber-frame trusses and the high open spaces it can create, cause extra cost. High open spaces are about 10-20% more expensive, partially due to the frame, and partly due to the extra cubic meters.
On the other hand, timber-frame trusses that create a used lived in, space actually reduces the cost, by maybe 10%. And additionally, you get extra cupboard or storage space for "free" (less than 160cm high).
This is the reason why the preferred ecoframe house design is a 1 1/2 story building with some open and some used space upstairs. While the open space is more costly, the used space reduces this relatively higher cost almost to "normal".
Interior surface finishing can have a big impact on the total budget, mainly because a house has so many square meters of it. For example, a basic tile may cost 10 €/m2, while some Morrocan tiles maybe 10 times that. Another example is clay plastering, which is very nice but compared to painting the surface maybe 5x more expensive.
The basic price quoted above includes basic surfaces, such as wood panels and painted Fiberboard.
Any water-based heating system will always be more expensive, just because of the base installation of storage and distribution. But air heating systems require a connected space and are not always desirable. Usually, heat pumps can only be used in small houses.
For a 70m2 house a heat pump may be 2500 euro, but a heat-water pump with floor heating, our recommended system for larger houses, 12000 euro.
Some people prefer earth heat, which is basically the same technology but require a hole drilled, that usually doubles the total cost.
A water-based pellet oven produces heat for the room and a central storage, while providing a live flame. It costs about the same as a water-heat pump and is a good alternative for medium-sized houses.
Basic windows are included in the price estimates above. But very large windows do cost a premium, especially when there are a lot of them, possibly with doors. These sort of modern windows may cost up to 3-4 times, depending on the house, this maybe 20 or 30 thousand euros.
Large windows can cause additional heating costs, especially when placed wrong, so we suggest to keep passive house guidelines in mind.
To summarize, an Ecoframe house can be built for almost the same money as a factory house. The extra is mostly better insulation and more healthy materials.
Extra features, like larger windows, more timber-frame or high-quality finishes will off course drive the price up. But a good balance can be reached when the timber-frame is used to create beautiful open spaces and useful loft-style space.