Joist hangers
 

Hi folks,


I am in the process of building a treehouse for our kids. I've have an outside frame of 2x8 rim joists, and i've managed to figure out the Hungarian for joist hangers (gerendapapucs - sweet!).


What I would like to know, as I know we have some builders within our ranks, is what size nails should I use to join the 2x6 joists to the 2x8 frame. The closest I can get to the correct hangers are 50x105mm (which satisfies the 60% of joist depth) but the only details I can find on nails on the multitude of treehouse sites I've looked at are based on American 10d or 16d double-dipped galvanised (tűzihorganyzott) nails. I can't get the transliation right to work out what to buy here.


Many thanks in advance
Carrot Cruncher

Re: Joist hangers
 

I'd recommend framing/ deck screws, not nails.

Re: Joist hangers
 

Hi Pulaski,


All my (exhaustive) research has led me to understand that screws don't handle shear forces as well as nails - although it appears, at least in some USA building codes including decking related sites, that screws are replacing nails but I'm strugging to find anything conclusive. There is a distinct lack of treehouse related literature in Hungary - unsuprisingly.


Thanks,
Carrot Cruncher

Re: Joist hangers
 

Assuming you don't envisage half the kids in the neighbourhood climbing into it simultaneously, I would worry more about flexing and vibrations pulling nails out, than screws shearing off.

Re: Joist hangers
 

gerendapapucs - OK 'beam slippers' works for me!

When I needed some joist hangers I found that they are not generally used and when I eventually found some there were priced at scarcity value - so I made my own!

Anyway back to nails. Nails here tend to come in thicknesses defined by the length so a nail of a given length will be of a fixed dia. If the joist hanger turns over the top of the beam and you can nail down then I would suggest 100mm nails otherwise if you are nailing into the side of the 2x8s then I think you will be a bit pushed to get 50mm nails of any decent thickness.

Most roofers use screws now for a lot of their work. there are 'structural' screws, usually with torx heads and expensive but they are designed to take shear, but you do need a decent impact screwdriver to make the job achievable without tears. But it is often quicker than nailing

2x8 and 2x6 (I assume we are talking inches) what sort of tree house is this? My table of floor joists gives a max span of 2.6M at 600 centres for a 2x6 joist - thats some tree house!

I presume you will be using OSB for the sheet material. I have had very good results with painting OSB with the acrylic thin coat render (as used for the top coat for external wall insulation). It goes on well, I have had some up for 4 years with no sign of deterioration and it comes in more colours than you can imagine.

Re: Joist hangers
 

Thanks Pulaski,


Those are valid points but i should hasten to add, that not wishing to harm the tree, and not having the kind of specialist hangers that the more advanced treehouse builders use the treehouse is actually a raised 12ft x 9ft deck supported by six posts 6ft off the ground at the front, 3ft off the ground at the rear with the tree growing through one front corner, with a hut positioned to the rear.


Similar to the below, but without the lower floor.


https://www.google.hu/search?q=handm...=1506452855635


Many thanks once again,


Carrot Cruncher

Re: Joist hangers
 

..it's on a slope...in case the above didn't add up

Re: Joist hangers
 

You're welcome. :)

If it's effectively a deck, I would definitely use deck screws, especially for the floor boards as nails always seem to work loose and need to be knocked back in or replaced with screws.

I use a corded deck/plasterboard screw driver, which works a treat with framing 2x's, boards, and sheet materials.

Re: Joist hangers
 

Unless you attach or clamp it to the tree or the supporting posts follow through and become the corner posts of the house (so that the wall sheets provide stability) then you will have to be careful to avoid racking and frame wobble

Re: Joist hangers
 

Thank you Peter_in_Hungary,


indeed the six posts do follow through and form all the corners to the hut and the front posts will hold the railings for the verandah, which in turn are attached to the hut. I didn't fancy wobbly railings. it has possibly been slightly "over-engineered" with regard to the timber dimensions but I would like it to last into the kids teenage years, and I can use it when I work from home.


I plan on standing a some water barrels across the deck for a few days t test it out before I let the hoards on it.


I really am very appreciative of all the advice that is available from all forum members.


Regards,
Carrot Cruncher

Re: Joist hangers
 

If it's any help, joist hangers and nails are available from Screwfix, who deliver to Hungary.

Delivery is two or three working days and is free for orders over 70 euros.