Low single layer deck build

melbs

I built a deck that sat flush with my back door, a task made difficult with a clearance of only around 150mm from step to ground. Here is how i did it.

Materials

• 10mm Dynabolts (galvanised)
• 10mm Coach Screws (galvanised)
• 10mm Hex Bolts (galvanised)
• 100 x 100 x 105mm M10 Galvanised Angle Bracket
• 200*45 Treated Pine (doubled for frame)
• 90*45 Treated Pine (joists)
• Pryda Half Stirrups
• Pryda Nails (for Joist Hangers)
• Pryda Joist Hangers
• Macsim 8G Deck Screws + Macsim Clever Tool (highly recommend)
• 90mm Merbau
• 35-40 bags of concrete
• G-Tape and Protectadeck timber protection tapes
• Deck Spacers

Total Cost ~$4,500

Before

After

Preparation

• Removed existing porch cover and cut down tree
• Excavated  an additional ~200mm of soil, giving myself ~350mm of total clearance

Drainage

• Dug trenches and installed a french drain, plumbed into an existing storm water connection (lucky)
• Geo textile fabric helps keep the slots on the Agi Pipe unclogged with dirt
• A thin layer of Scoria between Geo textile fabric and Agi Pipe also assists in keeping the dirt out

 

Ledger Board installed

• Sets the height of the whole deck (deduct the height of the deck boards!)
• 10mm Dynabolts were a bit overkill
• Be sure to have already marked where the joist hangers will be so that the bolts don't get in the way

Frame

• 200*45 Timber for frame. Double thickness (200*90) and joined using timber glue and Batten Screws
• Dig the holes for the posts/stirrups
• Dropped the bearers into place and screw together using Galvanised Angle Brackets 
• Using three Car Jacks, carefully adjust the frame so that it's perfectly level and flush with the ledger board
• Screw the Stirrups onto the Bearers so that they 'hang' above the post holes using coach screws
• Screw the frame to the ledger board using coach screws
• Fill the Holes with concrete and leave to set (make sure the concrete has a slight dome shape to allow water run-off)

 

Joists

• Use string line to mark the position of the Joist Hangers
• The joist hanger nails are much cheaper than the screws. You must use the special nails/screws from Pryda
• Clamping the joist hanger onto the joist with a C-Clamp made it a bit easier
• I used 12 nails per joist hanger

Decking

• Important: Run a belt sander across uneven areas of the deck frame, smoothing them so there won't be any unevenness when walking on the deck
• If exposed to the elements, use G-Tape and Protectadeck on the frame for protection (Took approx 30 minutes with a staple gun)
• 3D printed a jig for guiding placement of deck screws
• Use Car Jacks to press warped deck boards against deck spacers (see pic)

Decking Board Installation

• Best done as 2 person job

Person 1

• Use centreline of Jig to place directly under string line
• Predrill pilot hole
• Remove Jig and use Clever Tool to drill and countersink hole

Person 2

• Screw in deck screw

Completion

• Carefully trim the excess off the Merbau by running a Circular Saw across either end (I used a clamped piece of timber as a guide)

MitchellMc

Welcome to the Bunnings Workshop community @melbs. It's a pleasure to have you join us, and many thanks for sharing your fabulous deck project.

You've done a fantastic job constructing this deck and have spent the time needed to address many of the issues associated with a low-level deck. The drainage you've installed is excellent, and I even love the more minor details, like doming off the concrete footers. 

Your drilling jig is a stroke of genius and most certainly surpasses the scrap of timber I'd used with my deck. You should also add the spacing for the 140mm decking and start selling them! Not to toot my own horn, but I was pretty chuffed with the device I made for pulling warped boards into shape. I took an IRWIN 455mm Quick-Grip Heavy Duty Bar Clamps and modified one of the pads by attaching a 5mm spacer to it. The side with the spacer is slipped into the gap between the previous two boards for mounting. You're then free to compress the next board into shape whilst the clamp holds it in position as you screw it off. Anyway, I thought I was clever.

I'm sure you are really impressed with the results because I know I am. I'll be sure to point other members looking to build a deck to your post, as it's a really great example of a low-level deck done right. Well done, and I can't wait to see what you take next.

Mitchell