Planning and building a deck for alfresco

Hi @shawnvaz,

Spacing your joists 400mm apart would be fine to lay the decking upon. It's best to have the joists elevated above the ground to allow airflow to the structure and water to runoff. You could use the brackets you have now and elevate the joists 10mm off the ground. That would be much better than having them sitting directly on the ground. You might like to use some Macsim 75mm Mixed Hang Window Packers to assist in getting the correct height.

Please let me know if you have further questions.

Mitchell

https://www.workshop.bunnings.com.au/discussion/comment/16566#Comment_16566

https://www.workshop.bunnings.com.au/discussion/comment/70885#Comment_70885

Thanks a lot for sharing.

what is the span between each bracket? i am using 90x45 timber.

also, what is the gap between each timber? like i mentioned before 400mm is ok or can i extend to 450/500mmm?

How can i draw a plan? is there something i can use to draw up a plan so i know where each item should be placed and how many of each material i require?

Thanks a lot

Shawn

EricL

Hello @shawnvaz

The span of each bracket is relative to the length of your timber. The more brackets you have, the more support the timber has and therefore eliminates the possibility of having a bouncy frame. As my colleague @MitchellMc has mentioned having a space of 400mm for your joist is fine. If the area supports a 450mm distance, that spacing will work as well. I suggest having a look at this discussion - Low-level deck advice and suggestions by @oninpena. Their build area is very similar to yours and you might find some of our recommendations applicable to your plan.

There are many types of software you can use from Sketchup to Tinkercad. There are also online estimators that you can use to get an idea of how to lay your frame. I suggest drawing it with traditional pen and paper as it gives you a much better idea of how you will build the frame. You can also put side notes and reminders to yourself while planning the frame. I recommend having a look at this guide - How to build a low-level deck by @Adam_W. This guide will give you basic ideas of how to draw your frame. Once you finish your framing plan post it here. Our members can then have a look at it and make recommendations that will help you out.

Here is a link for ideas and inspiration: Inspiring low-level deck builds

Here are some amazing low-level decks that our Workshop members have shared.

Please keep us updated with your progress, we look forward to seeing your deck framing plan.

If you need further assistance, please let us know.

Eric

https://www.workshop.bunnings.com.au/discussion/comment/98629#Comment_98629

@EricL @MitchellMc

Excellent information

thanks a lot for sharing.

next question.

1. How do I make the frame. ie how do I screw everything together? do I use nails or screws? i am using 90x45 timber. when it comes to the edge which part should I overlap?

2. should i use joist hangers or just screw/nail the timber to the outer frame?

3. can i have brackets for the support at 500mm apart? i.e for a 4-meter length of joist I will have 8 brackets. is this too much? i want to avoid having to drill too many holes on my concrete slab.

4. if i do not have a 4-meter long piece of wood, can i use a 3m and 1 meter? how do i join them? do i need to have a special join or just place 2 brackets on the end of each wood piece where they join?

https://www.workshop.bunnings.com.au/discussion/comment/116073#Comment_116073

Hi @shawnvaz,

To fix the frame together, you can use Zenith 14 - 10 x 100mm Galvanised Type 17 Batten Bugle Head Timber Screws. You can also use them to join your joists to the frame. Joist hangers are convenient and might be needed if the frame is hard up against a wall and you can't screw through the frame into the end of the joists.

Joist supports don't need to be as close together as 500mm. If you look at a few of the projects contributed by our members, they tend to include supports spaced up to around the 1000mm mark.

You could join two sections of timber with brackets, and you don't need to create a special join if each section of timber is adequately supported. It would be a good idea to plan your joist supports out, so one is right next to the join.

Mitchell

https://www.workshop.bunnings.com.au/discussion/comment/126027#Comment_126027

https://www.workshop.bunnings.com.au/discussion/comment/132683#Comment_132683

Thanks a lot. Please forgive my drawing, i am no expert

im sorry, let me correct myself

i am using a 90x35 timer. will this work ok?

I am trying to deck the alfresco area. but extend the deck a bit over

this is the area i am planning to deck

request :

1. for 90x35 , what bracket should i use. (reminder i am building low profile deck. 130 mm from the concrete slab)

2. what spacer can i use?

3. towards the end of the deck i have a 70 mm fall. so there is an excessive gap. what can i use in this space? is there a bracket that can support it?

4. what should i use for bracket and bolt. (Eg. bracket, bolt to screw into concrete and bolt/screw for bracket to timber)

below is the pattern i am aiming

Thanks
Shawn

EricL

HI @shawnvaz

Thank you for updating us with your plan. Doing some quick math 130mm ( available space ) - 90mm ( timber frame ) - 19mm ( deck panel thickness ) will leave us with a 21mm gap. I suggest using Dunnings 40 x 80 x 40 x 5mm M12 Galvanised Angle Bracket. However, if you have an increasing fall you might have to use the next size up when you get to the center of your deck.

When you get to the end of your deck where the gap is 200mm I suggest using Dunnings 65 x 130 x 65 x 5mm M12 Galvanised Angle Bracket. To anchor the angle bracket to the concrete, I suggest using Dynabolt Galvanized. To mount the timber to the angel bracket, I recommend Bolt and Nut Galvanized in conjunction with Washer Galvanized. The size of the bolts, nuts, and washer you will use is based on the thickness of the angle bracket and the timber framing.

You will have to use a combination of timber offcuts and Macsim Fasteners 75mm Assorted Window Packers - 90 Pack. Let me tag my colleague @MitchellMc and see if he has other ideas on what bracket to use for your deck.

If you need further assistance, please let us know.

Eric

https://www.workshop.bunnings.com.au/discussion/comment/132683#Comment_132683

Hi @shawnvaz,

I trust @EricL's recommendations are useful, and I'd agree with what he's suggested. You'll have a little bit of room to work with the brackets on the sloped section. The brackets can be mounted at different heights onto your 90 x 35mm timber. I'll illustrate below. If the gap becomes too large, you'll need to switch to the larger bracket that Eric mentions.

90 x 35mm timber will work, but my preference would be to use 90 x 45mm timber as the deck will be stronger and more rigid.

Please let us know if you have more questions or need further assistance.

Mitchell

https://www.workshop.bunnings.com.au/discussion/comment/136765#Comment_136765

Thanks @MitchellMc

Unfortunately, i have already purchased the 90x35. i guess ill have to stick to it.

for the bracket. do i need to have 2 dynabolts? or one is sufficient?

can i use a threaded screw instead?

i heard bolts will cause the concrete to crack due to expansion, especially towards the end of the perimeter.

https://www.workshop.bunnings.com.au/discussion/comment/139560#Comment_139560

Hi @shawnvaz,

90 x 35mm is OK if you've already purchased it. You don't need to have two Dynabolts; one should be sufficient. You can use Ankascrews instead of Dynabolts, but both shouldn't be placed within 100mm of the edge of the slab. Dynabolts will only crack a slab towards the edge if they are placed too close. They will be acceptable to use everywhere else.

Mitchell

https://www.workshop.bunnings.com.au/discussion/comment/141467#Comment_141467

@MitchellMc @EricL

Thanks for the support.

I have laid out the frame. have not screwed it in as yet

just wanted to check. will this work?

im doing a picture frame, so i have left around 25mm from the wall so the deck board can overhang. is this ok?

the height difference is 20 mm.

could you please tell me what spacers i need to use and also which bracket will suite?

the side that falls away form the home is at a height difference of 70mm+20mm. so a total of 90mm

Also the side which i have placed the wood frame-spacer-spacer and frame, which piece should i support with the bracket? should i support both pieces or just the one?

what screws can i use for the 90*35 frame to build it together?

on the top end. i might not be able to use screws to attach the frame, what is my alternative?

Thanks
Shawn

https://www.workshop.bunnings.com.au/discussion/comment/142897#Comment_142897

Hi @shawnvaz,

The layout you have looks like it will work. Can I ask why you're changing the spacing as you move along the deck? You usually keep a consistent 450mm or equally divisible spacing across the whole deck. Having unequally spaced lines of screws would look a bit odd.

A 25mm overhang of that last board is acceptable. You don't need a spacer to accommodate for the 20mm height difference. You simply fit the brackets to the timber at the correct height as per my previous images. A larger bracket can be used on the section on the side that falls away.

If all the frame timbers are connected together, you can support either of them with a bracket or both of them if you wish.

Zenith 14G x 100mm Galvanised Type 17 Batten Bugle Head Timber Screws would be suitable for joining your frame together. If you can't screw them together, Pryda Joist Hanger Suits 35 x 90mm could assist.

Please let me know if you have any questions.

Mitchell

https://www.workshop.bunnings.com.au/discussion/comment/143896#Comment_143896

Thanks

Regarding the spacing, i am yet to set it. this is just a trial to see how it will look.

i will be placing it at 450mm apart. also for screws, im planning to use the https://www.bunnings.com.au/ekodeck-100m-pack-quickfix-concealed-kit-to-suit-timber-joists_p0089490

What do I use for the bracket to the frame?

Does it have to be cup head bolt or hex type?

of cup head, do the head side go onto the timber?

THanks
Shawn

https://www.workshop.bunnings.com.au/discussion/comment/144669#Comment_144669

@shawnvaz,

The Ekodeck 100m Pack Quickfix Concealed Kit is a fantastic seamless solution and allows you more flexibility as to where you position your joists. Just don't space the joists much further apart than 550-600mm as you start to end up with spongey deck boards.

I believe @EricL recommended a "Bolt and Nut Galvanized in conjunction with Washer Galvanized", and I'd concur. The Zenith M6 x 50mm Hot Dipped Galvanised Cup Head Bolts And Nuts would be suitable for your 35mm thick timber. Either cup head or hex head would be fine. The cup head bolt has a square section under it that will bite into the timber and stop it spinning when you do the nut up on the bracket side, so the head side goes onto the timber.

Mitchell

https://www.workshop.bunnings.com.au/discussion/comment/145234#Comment_145234

The bracket i am using is M12.

is it ok to use M6 bolt and nut to secure the timber to the bracket?

regarding bolting the bracket to the concrete. do I have to use M12 size or can it be an M10 or smaller instead?

Thanks

Shawn

Hi @shawnvaz,

My mistake. It looks like I've provided the incorrect link above. The Zenith M12 x 50mm Hot Dipped Galvanised Hex Head Bolts And Nuts would suit a bracket with M12 holes. You could drop it down to a Zenith M10 x 50mm Hot Dipped Galvanised Hex Head Bolts And Nuts, but I wouldn't suggest less than that.

For bolting the bracket to the concrete, I'd recommend the Ramset 12 x 70mm Galvanised DynaBolt Plus Hex Nut Bolt. Once again, you could drop that down to a Ramset 10 x 75mm Galvanised DynaBolt Hex Nut Bolt, but I wouldn't go any less than that.

Mitchell

https://www.workshop.bunnings.com.au/discussion/comment/16774#Comment_16774