Building the warshed thread

[almic85]

I can’t say I’ve seen straps to attach the walls to the floor before but cyclone straps to hold down roof rafters and trusses are pretty common in northern Australia where high winds and cyclones are a thing.

I’m sure you are already all over it by looking at your photos but for anyone else thinking about building something in high wind areas please make sure you get the right fixings (screws and plates) to attack external wall and roof sheets and make sure you put the right number of screws in to hold it down.

The last thing you want is for a metal roof sheet to come loose in a cyclone or hurricane as they do a very good imitation of Xena’s chakram.

 

[RonBSM]

I am so bookmarking and watching this thread.

Also hate you.

That view is epic. You absolutely have to have a bay window overlooking that view...

 

[Space Truckin]

@almic85. Curious to get opinions on the roof. Since this is just a shed and I want to keep costs down I was thinking of just using 3/4" plywood. glued and screwed shed style 'flat' roof. Instead of galvanized I was going to just do a membrane roof either with peel n stick or the stuff that is painted on. Seems popular here because there is nothing for the wind to grab, downside is it will need coating every other year due to UV etc.

Our cottage has galvanized standing seam. I wish i had more left over scraps. It held up amazing well to the 4 hurricanes ive been thru since living in this house.

 

[RonBSM]

I think only you can make that call, based off your local experience. For me the painting on a roof coating every year is a nothing thing. Its like half an afternoons work, for what sounds like the best option based on what you're saying.

 

[almic85]

@Space Truckin to be honest I don’t see a lot of plywood rooves down here in Australia. We almost always use tiles or corrugated steel for residential buildings (some of the fancier houses and bigger buildings have concrete rooves).

Most sheds down here are also built of corrugated steel/aluminium/iron or “fibro” for both wall and roof construction.

That said I built a treehouse and used plywood for the roof and it is doing fine, but I live in a temperate climate in a fairly protected place and don’t mind if the tree house leaks. I also didn’t seal it either because it’s open to the elements anyway.

I’d probably be more concerned about having a flat roof instead of a pitched roof or skillion roof as you will need water to run off instead of pool on top of it, especially if you are using thin plywood which might give way from the weight of the water if it pools or there is exceptionally heavy rain. The place your in looks tropical enough so the pitch only needs to be steep enough for water to run off and the eaves need to be kept minimal so they don’t catch wind and become a sail.

I’d also recommend checking the thickness of the plywood and spacing of the rafters against your local building code. It’s different all over the place to take into account local weather conditions, but you will usually see that the thinner the roof sheet the closer the rafters need to be to support the sheets. 3/4” ply is about 20mm so it’s a pretty sturdy sheet.

The below link is from a quick google search on roofing in the Virgin Islands and goes into a bit of technical detail, but ideally you should ask a local engineer or builder.

https://www.fema.gov/media-library-data/1522347818132-9fa4b38a90dc40b91fdb82eeb0307e98/USVI-RA3InstallationofResidentialCorrugatedMetalRoofSystems_V2_508.pdf

 

[Trafalgar Law]

I'll be following this thread with interest as I intend to start building my own warshed thingy in the next few weeks. Although mine will be built against the side of the house and the location isn't quite as exotic as yours.

 

[Space Truckin]

@almic85. FEMA is basically my day job! Ive studied so many mitigation manuals, they actually rewrote the regs on construction methods after studying the effects of the 2017 hurricanes here. Thats where the metal strapping floor to ceiling comes from!

Actually working on 2 FEMA grants one of which is specific to protection against wind borne debris.


The roof will be pitched. Around here Its referred to as a 'shed' roof that is pitched at 1 angle vs a hip or gable style roof. Its not the strongest but its cheap and easy! Should have that framed out this weekend.

Thanks everyone!

 

[RonBSM]

I'm pretty sure you need a 5° incline on the roof otherwise water can pool.

So it'll probably be advisable to have a slight pent roof in order to prevent water logging on the roof. Just remember to include loads of pics!!

I'm super excited to see more of what you're doing.

 

[almic85]

I guess I just lucked out doing a google search then.

As I said earlier you seem to have a pretty good understanding of how to put things together so I wouldn’t be too worried.

We would call that type of room a skillion roof rather than a shed roof or lean to roof. Pitch would normally be greater than 5 degrees (you guys use the term pitch to mean something different to us).

A flat roof for us is as it states a flat roof. Less than 5 degree pitch.

As a warning though having roofs pitched less than 15 degrees usually have ponding issues which can lead to capillary leaks (water running up through really small gaps between the sheets).

 

[Space Truckin]

Another quick update after a weekend of work.

Picked up some more materials. 3x6 rafters for the roof. This was not so much fun. I did not have any help and had to take my time to make sure I didn't kill myself.

I added a short wall section 1ft high to allow for cross ventilation. We get the trade winds out of the east. These large windows will be directly under the roof so will only be screen and hardware cloth to keep critters out. In the event of a storm I'll just put plywood over the openings. I put up some 2x4s off cuts for safety. Also here you can see some more lateral bracing for high winds - hopefully.

This was the first rafter. I put it into place to calculate where my cuts would need to be made and used the first piece as a template to cut the rest. The pitch should be close to 15 degrees.

My first cut didn't go so well... I over thought it a good bit and was going to have to cut out too much of the rafter.

After doing 9 of these the last one turned out a lot cleaner

The rest resulted in me climbing up and down the framing to get the rafters in place. As the sun was setting I got everything knocked out in the day.

Next week I will be working on securing the rafters with more Simpson Hurricane ties and getting the 3/4 plywood on the roof. Hope I have some help for that!

With most of the lumber used up the job site is looking more manageable. At least it gives me something to look forward to on the weekends spending time working on this and being with my 4 year old son.

 

[almic85]

Rule of thumb for notching rafters is that you can cut about a quarter of the width out and not affect the strength of the rafters, and yours look a lot shallower than that.

More out of curiosity what is the spacing between the rafters you have gone with? I can’t tell if it’s 600mm or 900mm.

Also out of curiosity what spacing did you go with for your wall studs and what height are they? There are a lot of nothings in there for a standard height wall.

 

[Stoof]

Looking great - it's sort of a war-pergola rather than a war-shed at the moment but it's coming along beautifully!

 

[Space Truckin]

@almic85. Hey! The rafters are 24in on center which is a tad over 600mm.

The walls are a few inches under 8ft. Tall. The thought behind that was so I could lay a whole sheet of T1-11 plywood on it. At 8x4. I'd have over a 2" overlap on the floor.

Studs are 16in on center. Not sure what nothings refer to, maybe what we call bracing? Horizontal pieces? If so. The 2x4s were originally used for scaffolding to repair the cottage post storm. They twisted pretty bad in the sun and the bracing was an attempt to straighten them out and ad more strength.

If this were to be a dwelling and built to code the entire structure should of been made from 2x6 lumber.

Thank you for the questions and suggestions. Been a learn as I go process. I wish I would of notched the rafters a bit more. There is material there to make a good connection with the wall but Im the type that always thinks...should I put 1 more screw in it....and my internal dialogue kicks in...well if we get hit with a hurricane and this shed is destroyed and your entire model collection is wiped out....would you not take a minute that 1 additional screw in!


Actually maybe Ill take my models into the shelter with me with the wife, kid and doggo!

@Trafalgar Law. Post up a build blog!

 

[RonBSM]

Add the screeeeeeeeeeewwwwww

 

[almic85]

Sorry. Autocorrect turned noggings into nothings.

Noggings are the horizontal timber’s between the vertical studs.

Building code down here is 1 nogging between each stud for walls less than 2700mm and 2 for walls over 2700 (actually max distance is 1350 apart so it is usually 2 in 2700 walls) for 450mm centre to centre studs. If studs are at 600 centres you basically add an extra nogging.

But that said our code doesn’t take cyclonic weather into account so more wont hurt.

I also have to do a bit of mental arithmetic with your timber sizings. 2x4’s are like our 90x45’s which is our standard timber for residential construction, so it seems like you guys upsize your timbers and number of noggings to take into account cyclonic winds.

 

[Punktaku]

Yeah, it would suck to get ... screwed... by a hurricane wiping out your collection.

 

[Space Truckin]

I believe if we evacuate Space Hulk maybe the only thing I bring with me.

And I'll think about the wife and kid if there is room.
ba dum tiss....
ok I'll get my coat.

Already have a concrete bunker / game room planned as an extension of the cottage. Budget being the main issue right now - also being halfway thru a kitchen reno...waiting on those contractors to come back after the plasterers finished. I'm tempted to install the kitchen cabinets myself but that's a whole other level of 'carpentry' I dare not attempt.
Still finding myself distracted during the work week (back in the office m-f as covid lockdown was irrelevant to my industry ) looking forward to building on the weekends and the eventual goal of having a space to properly 'hobby' again.

 

[RonBSM]

I am in no way hijacking your thread but it

1) Fits well with your thread
2) Doesn't warrant a thread of it's own

I've taken your lead, built the trusses I need to raise the height of the roof and change it from a gable style roof, to a pent roof which will be higher at the front and sloping down to the back. I'm adding 2 foot to the front elevation and 1 foot to the rear, so 7 foot to the top at the front and 6 foot to then rear.

Ripped out the old walls and floor which were not in a state to be allowed to remain, but the celotex wall and floor insulation is still good!!

It's going to allow me to build a workbench and have a little workshop instead of trying to work shit out in my gaming room....

So... many thanks for inspiring me...

Ruby was "helpfulling" me...

 

[almic85]

I am also assuming that you are going to attach the hurricane straps from the walls up to the rafters? Is that what the Simpson straps are you referred to earlier?

It’s less common here but we also occasionally put diagonal metal straps across the walls to help prevent lateral failures of walls. It works in a similar (but opposite) way to your timber bracing in the corners. The timber bracing will stop compression, but it (more likely it’s fixings) will let go in torsion, while a diagonal metal strap fixed into the side of the wall will provide a torsional strength and the fixings being at 90degrees to the force would need to shear on order to fail rather than just get pulled out.

 

[Space Truckin]

@RonBSM looking good the perspective of the last shot makes it look like a funhouse or a dungeon depending on which way yiur imagination goes. Looking forward to seeing it. I cant wait for mine to be completed so I can listen to Slayer, Ministry, Megadeth etc in peace.


@almic85 yes I think we are talking the same stuff. Simpson is a brand here but they are essentially all sorts of different galvanized hurricane ties and straps. Ill take pics this weekend. Got home from work at dark.

The diagnonal metal strap ones ones in theory should prevent lateral forces from 'twisting' the structure right? For sheer strength?