Timber-frame house design in Latvia: what to decide before design starts

In a timber-frame house design the key decisions are the construction method (built on site or from factory-made panels), the build-up of walls and roof, and the details that keep moisture away from the timber. They belong in the design, not on site, because in a timber-frame house mistakes stay inside the wall, where they cannot be seen later.

This article is for people planning a timber-frame house who want to know what to ask of the design.

How a timber-frame design differs

In a masonry house the wall both carries load and encloses the room, and insulation is added on top. In a timber-frame house the load-bearing studs, insulation, vapour control layer and wind barrier form one layered construction. The design therefore pays more attention to:

the order of layers in walls, floors and roof;
continuity of the vapour control layer and wind barrier at windows, floors and roof;
where timber meets the foundation and the ground;
routes for engineering systems, so that openings do not break the insulation layers.

The approval route is the same as for any private house: a single-dwelling house of up to 200 m² total floor area needs an explanatory report, a larger one needs a building permit and a building design in minimum scope.

Built on site or from panels

The frame can be built on site from sawn timber or assembled from factory-made panels.

Building on site makes it easier to change the design during construction, but the structure stays exposed to the weather for longer.
Panels are made in dry conditions and assembled on site in a short time. In return, every decision has to be made before production, and the design needs precise panel drawings.

If a specific factory will make the house, the architect needs to know at concept stage, because the manufacturer's panel sizes and details affect the layout.

What to decide before design starts

The construction method: on site or panels, and if panels, which manufacturer.
Heating and ventilation. In an airtight timber-frame house ventilation has to be planned together with the structure.
Facade and roof materials, because they determine the layer build-up and details.
Whether the house will be extended later. A timber frame makes that easy to allow for if it is known in advance.
The budget and which parts the client will build themselves.

Requirements the design must meet

A timber-frame house has to meet the same requirements as any residential building. In the design these come mainly from the Latvian building codes on the thermal performance of building envelopes (LBN 002-19) and fire safety of buildings (LBN 201-15), and from the municipal building rules. For timber structures the fire-safety solutions have to be shown in the design, so they cannot be left to the builder.

What a timber-frame house design costs

LINE 78 prices a timber-frame house like any private house: 55 €/m² for architecture and site layout or 75 €/m² for the full design with structures and engineering systems. For a 120 m² house that is 6 600 € or 9 000 €. Design work usually takes 3–5 months. Details: House design prices.

We design in BIM, so studs, openings and engineering systems sit in one model and clashes show up before construction.

Common mistakes

Picking a ready-made masonry design and trying to convert it to timber frame. Spans, wall thicknesses and details differ, so it amounts to a new design. On that choice, see Individual or ready-made house design.
Choosing the manufacturer after the design. The panel drawings then have to be reworked to the manufacturer's system.
Leaving ventilation for later. In an airtight house without planned ventilation, moisture stays in the rooms and the structure.

If you are planning a timber-frame house, contact us or see Private house design.