Building a Garden Office Advice Required

[imageel]

Dick,
Those house pictures were my previous residence, now wholly owned by my ex swmbo....... my new 'old' house is another project entirely, largely untouched 1930's one complete with rubber wiring and brown bakelite light switches!

Insulation on roof slow - have about 2/3rds done over the bank holiday but even today am still somewhat fatigued! I've decided Celotex is not very nice stuff to work with - it is incredibly dusty and made worse I guess because every sheet is being cut at least 6 times - next time I build anything will stick to stud work on 600mm centers and not 400 :?
Also the dust is quite gritty - literally every surface is covered in the stuff..
Actualy putting it up is not too bad, if cut reasonably accurately - am using a floorboard saw, it push fits between the rafters/studs and with a little expanding foam even the corner ones between the hip and 1st creeper are staying put!
Have mailed you re: doc
Cheers

 

[Markymark]

Ok

8 x 4 Sheets arrived now to get them up 10' . This should be fun!! I have made some ladder frames using 3 x 2 untreated timber.

I will let you know how it goes if I survive. I still need to mechanically attach the roof to the walls and even though we have discussed the bat fixings before in previous posts I ordered some twist ties and some truss clips but |I cannot get a succesful fixing with either. The problem seems to be that I attached the lower chord to the rafters at the wall plate so there is three m12 bolts and two 50mm sections of timber to attach to a vertical stud running directly under the rafter. The truss clips are only 50mm wide so wont fit and the twisted ties wont attach anywhere. Any othre ideas welcome.


Mark

 

[imageel]

Would skew screwing the assembly either side into the top plate work? Might need to use some largish ones to penetrate far enough...
Good luck with the sheets - I managed to get mine up by myself, however your roof is somewhat higher...
Cheers

 

[Cegidfa]

Mark,
For my roof I used one 7.5mm Rapier screw per position, 100mm long; straight down through the roof timber into the wall plate. I know this is not the normal method, but I feel that it is stronger than two side toshed nails or screws. The Rapier screws are designed for going directly into brick walls, so they are tough. You may need longer ones for your situation: there are other manufacturers of this type of masonry screw. They may be designed for masonry, but they fix in wood a treat; I used them in the bathroom to hold studwork to the large ceiling timbers. If you are concerned about rain in the top of the fixing, apply a squirt of silicone/mastic over it, I didn't worry. Go on make your life more easy 8)

Regards...Dick.

 

[bosshogg]

Mark...are you by any chance trying to fit the clips to the internal angle where the rafters, collars and wall header all inter-connect? if so try fitting them to the external where the rafter toes birds-mouth over the roof wallplates if it clear of obstructions. As you will no doubt have seen, the truss clips are very thin metal and easily bent to fit, however they look, as long as they perform. As I think I mentioned before, you also get single clips which allow you to fasten to all widths not pre-set at 50mm say.
If ness. you can also revert to thin metal joist hangers (Jiffy is one brand/name) and bend them however you choose, remember it's not the look but the performance you are interested in here as all will be covered over, either internal or external...cheers... bosshogg. 8)

No man is an island

(homer)

 

[Markymark]

Imageel - Thanks tried this with the original rafters with 6inch hardened screws but when I came to fit the collars I had to remove them and to my amazement 90% had sheered. I do not trust hardened screws under a sheer force anymore.

Dick - Sounds intresting I will take a look at these fixings. I wanted to fasten the entire roof stucture which was calculated to have a wind load of -1.5 tons at 80mph. This is a lot of upwards thrust.


Boss. I was going to try and fit the truss clips on the outside but was a little concerned they would be too close to the elements and thet they may fail in time. I also wanted to transfer the wall plate to the studs using metal straps but I can get some rolled metal band for this.


Mark

 

[bosshogg]

Mark... don't worry about the clips proximity to the elements, they were designed for this, here's something to look at_ http://www.google.co.uk/search?q=roof+t ... CDwQ_AUoAQ _
You can see roof-wall wraps here as well which will be perfectly acceptable for your use.
Just one word on this subject - most of the time specification for truss clips - hold down straps - valley clips and all the other paraphernalia fitted to timber frame buildings, is that most, not all of course, but most often is for insurance purposes rather than for the need of the structure, how many buildings 100 years old and more are still performing perfectly with not a truss clip in sight? this applies both to traditional build and timber frame alike (timber frames were in fact the earliest properly conceived buildings, after turf or mud construction, so not as new as some would think) ...bosshogg 8)

You can't fix a problem using the same thinking that created it...A.E.

(homer)

 

[Markymark]

OK Roof Boarded and Bitumen shingles ordered. FYI:- I managed to get a steel Drip edge as specified for these shingles. Cembrit supply one for £10 for 2.4m length.

Here is a few progress pics. Roof was sheeted with 18mm OSB 3 Sterling board. Then covered with tyvek Housewrap.

 

[Markymark]

Great,

Roof is being finalised. I need some help with the windows and doors. I purchased some white upvc windows and a white upvc french door. The windows fit the openings with about 5mm gap. The question is, I need to seal them to driving rain. I was going to fit them flush to the tyvek. I need to create a sill to stop water running back in the reveal and under the window. I was going to fit a piece of lead flashing to the underside of the window opening and then down the front of the cladding (Ship lap). The problem is that their is not enough space under the window to fit lead. I will try to get some photos to illustrate what I am trying to do.


Mark

 

[bosshogg]

Mark...these days it's normal to affix 50 x 50 batons all round the window, the thick ness of timber is matched to the fire stopping used to. form the cavity Allow at least 50mm of the window/door frames to stick into the slap & prepare the slap as follows - line the bottom of the slap with 'Visqueen' DPM allowing a turn up at each side, this should stop in the cavity between your timber frame walls and final cladding. It's important to bear in mind that the membrane (in your case Tyveck) is a secondary water proof skin should the outer cladding fail, similarly any cill flashing should be treated the same i.e. a secondary drip. The cavity created should be positively vented thereby allowing any secondary drips to dissipate, the real waterproofing should both be, and maintained, to the outer cladding. Hopes this helps...bosshogg

 

[Cegidfa]

Hi Mark,
Boss and I must have entered our entries together, his wasn't there when I started....Hi Boss - two minds with the same thought :smile:
For my cill pan I used Sika MultiSeal-S flashing tape. The water (should there be any) will run down behind the cladding and out at the bottom - which should be open, apart from insect mesh.
The wind and warmth will dry it out; this way you don't get water marks on the cladding face.
This is the American way, and they have far more experience of timber frame than we do.
Don't forget that the inside part of the cill pan needs to be turned up, or, just lifted a bit to create a slope. See below how mine is done, apart from lifting the back, which will be finished with the inside.

Hope that is of use....Dick.

 

[Markymark]

Nice job Dick. I was wondering how to flash over the ship clap cladding also?

P.S. The vented ridge went on a treat.

Some photos here...

Or for all images visit :-http://www.flickr.com/photos/markymark144/

Thanks Mark

 

[Cegidfa]

Hi Mark,

Glad the roof vent went ok. You have now caught me up as my vent is finished also :smile:
The shingles look good too. How did you overcome the fact that the shingle isn't wide enough
to cover the vent in one go?

Regards....Dick.

Just answered my own question by looking properly at the photo. You bought three tab shingles :roll:

 

[bosshogg]

Mark...I'm perplexed, the middle pic in your last post (floor construct) you appear to have in filled in between the joists with cuts of OSB, just interested why?...bosshogg

 

[Markymark]

Dick - The Cembrit 3 Tab Felt shingle seemed to fit just fine. They overhang the sides of the vent just slightly (10mm ish).

Boss - I paneled in between the floor joists so that I could keep the animals at bay and also to use to support the rockwool. I was going to panel the underside with full sheets but went for the more involved individual sections as I thought if any began to fail I would be able to repair individual sections. Do you think it will work?


Mark

 

[bosshogg]

Oh that was why, just make sure they can't fall through when joist shrinkage takes place and allow for expansion. netting and solid bat insulation would achieved the same rodent prevention, and cost less to boot, but otherwise spot on mate...bosshogg

You can't help a man who doesn't tell you what he wants :|

 

[Markymark]

Thanks Boss

The boards are sat on 19mm batons. Most have a 3/5 mm gap leaving 14mm to sit on all round.

The OSB is OSB 3 so even though it is not in direct contact with moisture it will get damp some days. I just hope the OSB 3 does not rot and fall out too quickly. I am over boarding with 22mm TGV P5 V31? Moisture resistant chipboard. I assume this stuff once laid wont be easy to take up so any work can be undertaken underneath from a individual panel.

Next stage is to fit the floor and then first fix electrics which I am undertaking myself then getting certified by a sparky.

I am cladding the imperial stud centres with OSB 9mm and then I am over boarding with 8x4 Bead & Butt MDF Panels to give it that boarded out feel. Not sure how to finish the roof yet.


Its great to have a watchful eye. This forum is absolutely great for us Hobbyists.

Mark

 

[Markymark]

Hi

I need to prepare to clad the outside of this building. I am using redwood ship lap timber that is VAC VAC Treated. Not sure what VAC VAC is the only reference is that the product used may be a arch timber preservatives product, but I am not sure? Can anyone spread any light on this treatment and what finishing stain I should use with it. Water/Alcohol based?

I need the name of a good brand of finishing stain that I can apply to this and will have maximum time before I have to reapply. Ideally I would like to apply this using a Spray gun for speed and uniform finish.

Any help gratefully received.

Mark

 

[Cegidfa]

Hi Mark,

Try this link for an explanation of VAC VAC.

http://www.wenbans.com/services-treatment.php

As to finish, we are going with Cuprinol Garden shades, as we have used that at our old house - on the fencing and bridge.
It lasted well, so we will try it again. It can be sprayed. Don't forget, paint all surfaces once, then fit it and paint again.
This way it will last longer - if more expensive. Coating all round reduces the chances of the bare back absorbing water/vapour and causing
cupping and splitting with seasonal shift. I got this from watching Tom Silva on This old House...err...many years ago.

Regards....Dick.

 

[Markymark]

Thanks Dick. I think I am on the right track.


Mark