Renew or replace old floorboards?

Hello,

we are currently carrying out a complete renovation of a detached house built in 1956. Originally, we had planned to refurbish and preserve the old plank floor on about 100 m² (ground floor and upper floor) together with the approximately 60 m² in the attic (which is to be converted), which has so far been covered by carpet and thus well protected. The plan was to use wall heating behind clay plaster in the rooms with the wooden floor, and underfloor heating only in the rooms that will get new floors (hallway, bathroom, utility room).

Now doubts are arising: according to the craftsman’s assessment, it is not certain whether the plank floor (currently 2 cm) will still be thick enough after sanding; and the question is whether financially we would be better off with a new floor in the end.

We have two offers for refurbishment (sanding and oil sealing): one for €70 gross per m² (about €11,000), and one for €10,000 gross for everything. In addition, the option of wall heating plus clay plaster would definitely be more expensive than underfloor heating and lime plaster on the walls. We would get new oak planks from the local store starting at about €60 / m², so for the ground floor and upper floor that would be about €6,000 plus installation costs. We would definitely keep the floor in the attic.

How would you weigh the options, also considering the condition of the planks (see pictures)?

Many thanks!

Hello questioner.
As I can see from the photos, the old floorboards lie on a substrate, so they are not nailed on battens?
If that is the case, the thickness of the boards is hardly significant anyway, since there can be no sagging under load.
And a renovation of the old boards with a material removal of an estimated 3mm would not be very meaningful either.
The wooden boards still appear to be in excellent condition in the photos.
Therefore, there is nothing against a comprehensive renovation of the board surface!
My personal recommendation for surface protection: an oil/wax mixture (no K-sealant)
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Regards and good luck: KlaRa

New oak floorboards would be available in the local store from about €60 / m², so for the ground floor + upper floor that would be €6000 plus costs for laying.

How much does the laying cost? In the end, all items are calculated.

How would you weigh it up

To be honest, I would do it myself if other things in a renovation, done by a professional, give me peace of mind. Nothing more needs to be said about the floorboards if Klara as a professional has already explained it well. Why do it yourself? On the one hand because of the costs, on the other hand I wouldn’t want to miss doing some things myself. Especially tasks like these, where after moving in you can be proud of the work every day, offer a lot of satisfaction and a good and personal connection to the house.

I would renew the floor, as apparently there is no insulation underneath.

Thank you very much for your assessment!

Yes, there is a cavity beneath the floorboards, they rest on beams about 5cm thick, and underneath there is some kind of wool. I can take photos of it over the weekend.

Exactly, if we keep them we would only oil them.

Here you can see the floor structure more clearly; the floorboards are nailed to battens, with some insulation underneath.

At the moment, one idea is to refurbish the floor on the ground floor (there is [Wandheizung]) and to replace it on the upper floor (there is [Fußbodenheizung]).