Comfort and technology in a solid, energy-efficient wooden house

We continue the series of presentations of wooden houses with a construction about which Vlad Liteanu, from Litarh, says it is a real school house. The way it was made isolationThe materials used, the construction of the trails, the ventilation with heat recovery, the heating system used, can all be used to teach a lesson on how to build a highly insulated and earthquake resistant wooden house. The house, owned by a group of young IT-engineers who were involved throughout the construction (often even working alongside the Litarh team), is a projection into the future. The water shuts off automatically if a pipe bursts, the heat can be turned on from your phone before you leave the office, and other such "sci-fi". We spoke to both the builder and the owner, and the article below is the rather technical presentation of the house built in Voluntari, near Bucharest.

wooden house

Project

Cătălin Ciurea and his wife are IT specialists and wanted a house where this would be visible. But more than that, they wanted to be able to get involved in the construction, in the choice of materials, to understand why one material is better than another, in short they needed a builder they could communicate with.

"We had the project detailed by the strength designer at the level of exact material quantities from the catalogues of the profile companies (eg: Rothoblaas, Egger) and drawn in a specialized software. I emailed this kit to all the companies I found online that would build wooden houses."

They contacted several companies, but the best communication was with Vlad Liteanu. They talked to him, paid him a visit and received a first offer. In order to be convinced that they were making a good choice, they also talked to the owner of a house in Bucharest built by Litarh. They understood that they could talk to Vlad, that they could get involved in the construction as they wished, and this made them choose to build their house with Litarh.

The discussion with the architect followed. "We proposed something, but the architect recommended something else based on the size and shape of the land. We also used elements from our original proposal, but in general we went with the architect's version. We discussed this version and made adjustments here and there."

The house, with a usable area of 130 m², has a ground floor and first floor. The ground floor was designed as a meeting place and the first floor as a resting place. On the ground floor there is a generous living room of 41 m², the kitchen of 9 m², an office of 5.3 m², the entrance hall and a bathroom. Upstairs there are 3 bedrooms, 2 bathrooms and a technical room. The 15 m² master bedroom has access to one of the bathrooms and the technical room. The other two bedrooms are smaller, about 11 m².

Works in the Valea Moldovei factory

When all the details of the project were ready and the land prepared for the new house, construction began. This time the walls were mostly built at Valea Moldovei. Unlike when they were built 6-8 years ago,house in France and the one in Arad, the factory was much better equipped, having state-of-the-art prefabricated wall construction systems, purchased in Germany.

First of all it must be said that it is a very well insulated house. In addition, it has a state-of-the-art material from Egger which allows moisture to escape from the wall structure to the outside - i.e. it is a perspiring house. Why is this a good thing? Because if there's any moisture left in the structure it can escape to the outside, which is very important for a timber frame house. Moisture that remains inside can over time lead to mould or even wood rot.

The walls were made entirely in the factory, and their structure, from the inside out, was as follows:

chipboard
technical space for pipelines, routes, etc.,
50 mm insulation
OSB structure board
200 mm slab of 60/200 mm studs with 200 mm thick basalt wool insulation
15 mm DHF (material allowing vapours to escape)
150 mm high-density basalt wool insulation
vapour dispersion film (anti-condensation)
ventilation ruler
heat-treated wood panelling.

wooden house

The roofing was also worked on in the factory, but not entirely, the trusses being assembled on site. Structure:

gypsum board
technical area
OSB board
vapour barrier
rafters 60×250 mm
250 mm rolls of basaltic wool
aster
High density DHF
high-density basaltic wool
vapour dispersion film
ruler
plank ashlars
galvanized sheet metal.

wooden house

The house, almost finished in the factory, was loaded onto a truck and taken to Voluntari to be assembled on the poured and reinforced foundation. The whole thing was much simpler compared to a house being built from scratch on site. Catalin says that from the time they bought the land to the time they moved into the house was three years. Of these only 1 year was needed for the actual construction, of which 3 months were not worked on for various reasons. They moved into the house a few months ago although there was still work to be done on the finishing touches and they still had a number of systems to install. They continued to work "from the inside" as they would say, but did not finish. The arrival of the baby in their lives slowed the pace and changed their priorities a little. 🙂

wooden house

Insulation

Apart from the IT facilities I'll tell you about in a moment, the house's strongest asset is the insulation. Three types of mineral wool were used - glass wool, semi-rigid basalt and rigid basalt - and extruded polystyrene for the base. Because the Environmental Fund Administration does not consider these materials organic, they were not able to apply for funding under the Green House Plus programme, as they wished.

The high-density basaltic glass used creates a thermal lag, which makes it very difficult for the house to heat up even if the sun beats down on it all day. Heat transfer between the sun-heated wall and the interior is very slow so it doesn't get muggy on hot summer afternoons. Instead, the heat arrives at night, when it's needed, and at a much lower level.

In addition to the insulation in the walls and roof, the foundation and plinth were insulated with 10 cm polystyrene. They considered sealing with vapour barrier and anti-condensation foils so important that Catalin and the family were directly involved in making sure it was done thoroughly and rigorously.

To make sure they achieve energy efficiency, they have invested around €10,000 in insulation.

Heating systems. Home energy efficiency

For heating the house, they chose systems that are mainly used in office buildings, which meant planning and executing the installations adapted to a house. Air-to-air heat pump heating and heat recovery ventilation - a system certified byPassive House Institute (Passive House Institute).

The house is energy efficient, but it is not a passive house. The calculations were made for a consumption of 50 kWh/sqm/year, but as it hasn't been a year since they moved into their new home I can't say yet if it fits.

"We worked with a Romanian architect, Dr.arh.Adrian Moleavin, certified by Passive House for passive house design, and we started with the idea of making an efficient house, but not passive. We are of the opinion that the investment is not justified to achieve the passive house standard."

The orientation towards the sun was the essential element for placing the house on the land. The same idea was used to position the rooms, which face south, including the kitchen. The bathrooms and the technical room are on the north side, "behind" the rooms. The effects of the decision were visible in winter when sensors were used in the rooms to track temperature changes and receive high or low temperature alerts.

A very good insulation of all water and sewer pipes in the house was done. The windows and the front door were chosen for their quality and are also Passive House Institute certified. It was quite an adventure to plan, design and build them, with one of the windows weighing approx. 440 kg and the other 330 kg.

I asked Catalin if he could give us an annual energy consumption given all these investments made to get an energy efficient house.

„At the moment I can't give a cost because we haven't actually lived in the house for a year. We have an energy certificate done on exact figures from product catalogues we have used. The certificate says that we will consume about 29kWh/sqm/year for heating/air conditioning/mechanical ventilation. The only energy resource we use is electricity. That's 3770 kWh/year or about 1880 RON/year, not counting hot water."

IT systems in the home

As I told you at the beginning, the house is owned by IT-people and this is very visible. There are things that we wouldn't even think of, but that Catalin considers very important and he finds it practically inconceivable to have a house without such systems.

"I find it essential to be able to turn on the heat/cooling remotely. It's an essential element of comfort in my view. It means knowing what temperature you have in the house when you're away. That's where the elements I focused on - monitoring and alerting - come from."

Let me tell you, briefly, what are the elements that Catalin is talking about:

Temperature sensors installed in specific areas of the house to monitor changes in temperature and humidity. They have been set up to send alerts to your phone when the temperature is above or below a certain threshold.
The air conditioners are equipped with Wi-Fi controllers and can each be switched independently into heating or cooling mode.
The recovery ventilation unit was specially purchased with remote control mode (on/off/turnover etc.).
The outboard rollers have a wind sensor that controls their lifting if the wind is too strong and there is a risk of being blown off the rails.
Smart sockets with consumption monitoring for water pumps in the house to stop their supply in case of a breakdown (broken pipe, for example).

Catalin says it's far from over. There are many other systems they want to experiment with, but they haven't yet got around to focusing on them. He's glad he was able to use good quality materials and products, that he worked with a builder he could collaborate with so he could put his ideas into practice, that he has the strong, solid, energy-efficient wooden house they wanted.

Although they already live here, they told us that there is still a lot to be done, both to the house and the yard. They suggested we come back when everything is ready. We will do so knowing that all sorts of surprises will be waiting for us.

wooden house