Terrace substructure on wood weather-resistant

Hello everyone,

Our terrace (approx. 38 m²) will be located above our garage entrance, essentially on the 1st floor. We have a steep slope, so the basement is planned with a double garage and above it the terrace. Accessible from the living rooms.

Regarding the actual concern. The main substructure from the timber construction company for the terrace/carport will be wooden beams. On top of that, Nordic pine with resistance class 1 will be used. The "smaller" substructure naturally made from the same material, 45x70 squared timbers. Then the decking boards go on top.

Now there are 3 layers of wood on top of each other. The decking boards + the small substructure will be mounted klassically with Terrafix spacers and then hopefully only need to be renewed after +15 years.

QUESTION: How can I properly and weather-resistantly attach the squared timber substructure to the beams? At an acquaintance’s place, the beams at the screw points were severely and deeply rotted. I don’t want to have to completely renew the beams in 20 years as well, but hopefully only in a later period!

What solution would you suggest here? The timber center also offered me rubber granulate pads. Should I use those? Is that enough?

Thanks a lot for your tips!

Konstantin

Pine (also thermo-pine) will never reach resistance class (durability class) 1. If your supplier claims that, throw him to the wind! Class 1 would be, for example, teak or ipé. Thermo-pine would at best be at 3.

As for the durability of the construction:

- Ventilation
- Roofing
- Aluminum instead of wood as substructure

The pads would at best protect the "small" substructure. But it probably wouldn't hurt and costs almost nothing

Pine (also thermo-pine) will never reach resistance class (durability class) 1. If your supplier claims that, throw him to the wind! Class 1 would be, for example, teak or ipé. Thermo-pine would be at best class 3.

Regarding the durability of the construction:

- Ventilation
- Roofing
- Aluminium instead of wood as substructure

The pads would at best protect the "small" substructure. But it probably wouldn’t hurt and costs almost nothing.

Hello Dr. Hix,

thank you for your answer. Nordic pine has a silicon compound and becomes petrified under high pressure. The mineralization that arises makes the pine more durable. I am switching to this product because I would like to have this silver-gray tone and teak etc. is not an option. It is also rather a newer product on the market. At home, we have teak, so I am familiar with this wood on the terrace.

Back to the substructure. The whole thing is sufficiently ventilated! Also, the terrace is located on the south/south-west side.

Unfortunately, the substructure for the terrace, above the garage entrance, remains made of wooden beams. In your opinion, should I put the pads on the wooden beams and then screw the substructure on top? Do I understand that correctly, see sketch attached.

Would it not be feasible to lay the entire substructure with decking boards floating on the entire beam structure?

Thanks and best regards

We often build piers at harbors. A few tips on the substructure to achieve long durability. Get yourself Carbolin. It is available at the building materials store. With it, you coat generously, really generously, both beams and the lower battens. For pads, which are very important, use pieces of tar paper. If you can somehow get genuine Carbolineum from an eBay shop, that is clearly preferable. But please paint it with gloves and goggles then.

We often build piers at harbors. A few tips for the substructure to achieve long durability. Get yourself Carbolin. It is available at building material suppliers. You brush it generously, really generously, on both the beams and the lower battens. For pads, which are very important, use pieces of tar paper. If you can somehow get real Carbolineum from an eBay shop, that is clearly preferable. But then please paint with gloves and goggles.

Hello Nordlys,

thanks for your tip. Is the Carbolin only available in brown or also in white?
If only brown, then I can only paint the top side of the beams, as the rest is otherwise white.

I will take a closer look at everything.

Carbolin is always brown black. Why, is the substructure visible?