Can I use timber battens for wall framing for a cubby house?

[Raymo16]

Dear Workshop,

I am planning to build a cubby house for my daughter.

from the research I’ve done, typically the wall framing is built using a 70mm x 35mm treated pine.

i am concerned that if i use this size of timber, the walls will appear too thick (relative to the size of the cubby) and unnecessarily reduce the internal floor area.

I’m not wanting to build a large cubby. For reference, I have made a 1.8m x 1.5m base for it to sit on.

Could I build the wall framing using 42mm x 18mm pine? Or is this going into territory where stability / integrity will become an issue?

[TerryN]

Hello Raymo,I used 70mmx45mm batterns on one I did for my grandkids a good while back,as that is what was laying around on  our site.It is also close to the size that you are considering.1160mmx1250mm.I didn't put a tin roof on it though as it's under a pergola area and weather proof,although it wouldn't be hard to screw a couple of sheets onto it if needed.I just used some pine lining boards out of the skip bin to line the walls and ceilings.I used leftover treated pine decking boards for the door and floor (didn't take a snap of it as it has some off cut carpet on it.)Regards Terry.

[JacobZ]

Hi @Raymo16,

Thank you for your question about wall framing for a cubby house.

Unfortunately, you could not use 42x18mm to create any kind of supporting frame, especially if there was going to be a roof on it. Having handled thousands of lengths of 42x18, which is a profile used for timber trims, I can say from experience that they can and will snap quite easily.

The smallest profile of timber that can comfortably be used as the supporting frame for a structure is 70x35. 

Yes, you would be losing 70mm of space on either side, but for the safety of your children and your own peace of mind, this is an unavoidable loss of space.

Let me know if you have any further questions.

Jacob

[Raymo16]

Dear Terry,

Thanks for the information and photos!

[Raymo16]

Dear @JacobZ,

Thanks for clarifying! 

Would the 70x35 also be suitable for framing the roof?

[JacobZ]

Hi @Raymo16,

In house construction, you would usually use larger timbers, engineered timber products such as LVLs or prefabricated trusses for roof framing. In a smaller application like this, you can reduce the size, but 70x35 is still too small a timber to support a roof.

Manufacturers of corrugated iron sheets will call for 90x35 timbers at a minimum. I'd suggest you use 90x35 H3 framing pine for your roof.

Let me know if you have any further questions.

Jacob

[Raymo16]

Dear @JacobZ,

Thank you for this!

I'm sure i'll be back with some more questions as I try to figure out how to build this thing.