Gap in Summerhouse join

[johnscales]

Hi all.
My summerhouse which was built a couple of years ago has recently developed a gap in one of the uprights. It must have happened within the past 2 months because I had artificial grass laid just 2 months ago and it was fine for at least a month since.
Gap is about 5mm wide.
Not sure what has caused this but am wondering what would be the best way to address it.
Current idea is to fill the gap with deep wood filler, let set and re-screw through to the adjoining support.
As an aside, I don't think it has anything to do with damp but just in case I am running a dehumidifier (desiccant) for a few days before I insert the wood filler and the length of the of the split feels dry to the touch.

I am posting here because I am hoping to find out whether there is any other approach I should consider. I was toying with the idea of taking the weight of the roof and trying to 'pinch' the two affected supporting sides together so that the gap is less to begin with but I don't want to disturb anything structurally if at all posible.
Also the roof itself is extremely heavy since it is covered with a heavy hexagonal shingle which would make this approach tricky.

Any thoughts or advice would really be appreciated before I dive in.

I've attached a pic from inside looking out. It's about a foot long from the base upwards.

Thanks
John

 

[^woody^]

Put some screws in to hold it better than nails do. Fill with mastic.

 

[johnscales]

Thanks woody.
Mastic/wood fill first, then screw through?
Uploaded another pic

 

[^woody^]

If screws will pull the panels together then fill it first. Otherwise it don't matter as the screws are just to stop it getting worse

 

[domdee]

could try clamping it first to see if it pulls tight, then screw once closed up by the clamp.

 

[johnscales]

Hi all. Just thought I'd post an update of the situation and the solution to this problem in case it helps anyone in future.
So I went out and bought a Draper mini moisture meter from toolstation to check the moisture content of the flooring of the summerhouse (SH). Turns out I had a lot of mosture in the wood to the rear of the SH (25% in places).
I have a medium sized storage container behind the summerhouse and the lid which accesses the container slopes towards the SH. My guess is that when it has been raining the water has been running off on to the floor at the base of the SH over time and has worked it's way upwards through the wood. On to the fix.

First I have repositioned the storage unit so that the slope now faces away from the SH. This should stop rain pouring off of it and gathering at the base, then being soaked up into the wood.
Then I bought a dehumidifier (meaco dd8l) to use in conjunction with the convection heater I already have in the SH. I have been experimenting with the set up for the past week and found that a lot of water was being pulled out of the air but the moisture content of the floor barely moved (1% over 4 days). Yesterday I pulled an old fan heater out of storage and used it instead of the convection heater, directing it at the floor. Using this in conjunction with the dehumidifier has given results of 0% moisture in half of the affected area oer a 48 hour period.
I am very pleased to have found a solution which works for me and likely to work for many others that find themselves with a damp floor problem.

 

[johnscales]

Further update. Entire floor is now at 0% moisture having left the fan heater lilted towards the floor for a further 48 hours.

 

[domdee]

What about the gap?