Dom's workshop build

[DomD]

Wall insulation done

Just adding the membrane now but it's not going too nicely around the corners. I may just make a cut and seal it with the tape?

Will hopefully finish later tonight.

 

[DomD]

Have now done membrane on roof and walls - just gable ends to go.

First I put it on the walls:

Then I finished boarding the roof and added insulation

Today I did the roof membrane. Really hard to get right, didn't help that I didn't realise you put battens on as you went, but the wind was what really made it tricky.
This was the first side I did, not perfect but I think the creases are exaggerated in the photo:

The back side went on perfectly:

Then I used a makeshift 'roofing ladder' to do the taping:

I then added a ridge sheet but it was too dark for photos.

I have left this tonight with no battens on, though there are quite a few staples and the sheets are taped; hopefully it survives. I will add battens tommorow though may have to be temporary as not 100% on spacings.

I did have to staple below the overlap due to the high winds, will this impact the waterproofness of the membrane?

Dom

 

[mindthatwhatouch]

Hi Dom,
Cracking along nicely.
I may be a bit late with this but for the membrane, if you nail a metre length of temporary batten through the start of the membrane (ie on the fascia for the roof, or around the corner on a wall) leave the nails proud so you can remove it later. It holds the fabric nice and tight when you lay it out then do the same at the other end of the roof or wall. Once you’ve battened it out you can remove the temporary batten and cut the excess membrane.
It’s one of those jobs that an extra pair of hands goes a long way, especially when it’s windy.

 

[MikeG.]

......It’s one of those jobs that an extra pair of hands goes a long way, especially when it’s windy.

It's always windy when you use a membrane! It seems to be one of those immutable laws of nature.

 

[DomD]

Battens now on the membrane, rained last night and dry inside.

Now I just need some doors - you can see the start of what I was doing in the interior photo.

 

[John Brown]

Sorry for the dimb question, but dou you nail the battens on through the membrane?

 

[DomD]

Sorry for the dimb question, but dou you nail the battens on through the membrane?

I did and I think that is the right way as the battens need to be attached to the roof structure.
I assume the batten forms a seal, and water instead runs down over the membrane in the sag between the rafters.

 

[DomD]

For the door I am planning on a structure of OSB->insulated 4x2 frame-> shiplap. I think I will try to bend the hinges as demonstrated on Mike's workshop thread.

Is it a good idea to have breathable membrane over the frame (and perhaps a batten ventilated void) behind the door cladding? This would thicken the door quite a bit.

Also, what paint/primer should I be using over the OSB and how should I apply it? I have heard the cheaper HVLP spraters work resonably, though I could just use a roller.
Thanks

 

[MikeG.]

Just be careful that door isn't too heavy. It sounds a monster.

 

[DomD]

Just be careful that door isn't too heavy. It sounds a monster.

I will see - maybe can leave the OSB off it.

I think I will use a couple coats of white masonry paint on the OSB3 - I've read this way I won't need to prime? I have also seen bedec barn paint recommended - unsure of how reliable any of this information is!

 

[MikeG.]

Painting OSB (inside the building) can be done with the cheapest emulsion you can lay your hands on. There is absolutely no point using expensive paints such as Bedec or a masonry paint. Save Bedec for outside.

 

[DomD]

Painting OSB (inside the building) can be done with the cheapest emulsion you can lay your hands on. There is absolutely no point using expensive paints such as Bedec or a masonry paint. Save Bedec for outside.

But will it need primed if I use cheap emulsion? If so what with?

Thanks

 

[MikeG.]

No, no primer required. The first coat should be watered down a bit.

 

[DomD]

Slower progress - I did install the windows:

Only to decide the white really doesn't fit with the building... I will be getting some custom sized wooden ones; if anyone has used any companies for windows I would be open to recommendations.

Then I made a door and similarly dislike the result; Mike was right about the design being too heavy so I will replace with a shiplapped/t+g door.

I also finished off gable insulation:

Onduline has been ordered for installation next week. Am I correct to assume the 'sag' in the roofing membrane would allow insects into the void below the onduline? If so how do I seal this? The corrugation profile will be sealed with a foam eaves filler above a batten.

Could the ridge also act as an opening?

Thanks

 

[beech1948]

I can not see from your last picture but Onduline will sag between the roof members such that over 5 yrs you will have a 3" to 5" sag which collects and holds water. Onduline has no strength to resist this. Guess how I know this.

If still using Onduline then you need to provide either ply (1/2") or 3/4" OSB for the Onduline to sit on.

 

[DomD]

I have begun installing the onduline:

I have looked online and as far as I can tell I need eaves but not ridge ventilation (see http://www.nhbc.co.uk/Builders/Products ... s2019/#317). I will use comb fillers at the eaves and just fill the ridge profile with foam fillers.
Eaves shown here where gutter will go:

I damaged the sheeting a few times during installation:

Is there a good way to repair this? I am planning on using roof and gutter seal.

Thanks

 

[MikeG.]

Yeah, that's your best answer.

You seem to have plenty of battens in support, so sagging won't be an issue. However, I'll warn you now that your roof will be black, not green, within 5 or 7 years. I did a workshop of mine in green, like yours, and it was identical to the black stuff by the time I sold the house.

 

[DomD]

I can not see from your last picture but Onduline will sag between the roof members such that over 5 yrs you will have a 3" to 5" sag which collects and holds water. Onduline has no strength to resist this. Guess how I know this.

If still using Onduline then you need to provide either ply (1/2") or 3/4" OSB for the Onduline to sit on.

I have supported it with battens at half the specified span for my pitch (had to due to membrane requirements). They guarantee it for 15years if installed correctly and some say it can last much longer; hopefully that means I'm ok!

 

[DomD]

Yeah, that's your best answer.

You seem to have plenty of battens in support, so sagging won't be an issue. However, I'll warn you now that your roof will be black, not green, within 5 or 7 years. I did a workshop of mine in green, like yours, and it was identical to the black stuff by the time I sold the house.

Hmm that's a shame as the green costs a fair amount more; it will be nice to have it at the start anyway, the idea was to blend in with the trees.

 

[MattyT]

Great project. I would like to build a smaller version for my garden.