Gather your supplies
- Post – 900 x 90 x 90mm H4 treated pine (9)
- Bearer – 3600 x 140 x 45mm H3 treated pine (3)
- Joist – 2515 x 140 x 45mm H3 treated pine (20)
- Blocking – various lengths x 140 x 45mm H3 treated pine (16)
- Floor sheet – 3420 x 900 x 19mm particle board (2)
- Floor sheet – 3420 x 900 x 19mm particle board (1) n Decking – 3600 x 90 x 22mm treated pine decking (27)
- Side deck skirting – 2587 x 90 x 22mm treated pine decking (2)
- End deck skirting – 3644 x 90 x 22mm treated pine decking
- 3.6 x 3.7m shed kit
- Wall lining sheets – Various sizes cut out of 2400 x 1200 x 12mm MDF (8)
- Pegboard – Various sizes cut out of 1830 x 1220 x 4.8mm masonite (3)
You’ll also need
Hammer; wooden pegs; stringline; bricks; tape measure; marking out paint; posthole digger; power saw; sharp chisel; drill; 85mm galvanised batten screws; spirit level; framing nail gun and nails; chalk line; 140mm joist hangers (28); timber connector nails; multigrip angled brackets (4); concrete (2 bags per hole); wheelbarrow; shovel; construction adhesive; 50mm screws; sledgehammer; decking nail gun and nails; 5mm plastic packer; Cabot’s Deck and Exterior Stain (we used Mornington Dew); stain applicator; oil-based primer (we used Dulux Precision High Opacity Stain Blocker); Dulux Weathershield low-sheen acrylic (we used Wave quarter-strength, Wave full-strength, Camisole); paintbrush, roller and tray; chalkboard paint (we used Dulux Design Coloured in Zuni); interior acrylic (we used Dulux Wash&Wear in Surf Wash and Iced Vovo); undercoat (we used Dulux 1 Step Primer Sealer Undercoat); durable exterior acrylic (we used Cabot’s Timbercolour in White)
STEP 1 To set out back and side position of shed, hammer wooden pegs into ground at required distance from fence, here 900mm. Stretch stringlines between pegs. Make tight and check square.
STEP 2 From where stringlines intersect, use bricks to measure 3m on back stringline and 4m on side. The diagonal measurement between these points should be 5m. Adjust position of stringlines if necessary.
STEP 3 Working from stringlines, use marking out paint to mark positions for posts. This 3600 x 5165mm platform is supported by 3 bearers, 1 at each end and 1 in centre. Each bearer is supported by 3 posts, one 135mm from each end and 1 in centre. Use post-hole digger to dig holes 500mm deep for each post.
STEP 4 Mark 1 end of post for 130 x 45mm rebate. Set power saw to cut 45mm deep and run across post at bottom of rebate and then a number of times through timber to be removed. Knock out waste timber with hammer and smooth rebate with sharp chisel. Repeat for remaining posts.
STEP 5 Create bearer assembly by putting rebate in post over bearer. Predrill, then screw through post into bearer using two 85mm galvanised batten screws. Attach all posts to bearer. Repeat to create 2 more bearer assemblies.
STEP 6 Put bearer assemblies into holes. Make bearer at end of platform meet end stringline. Ensure ends of all bearers are in line with stringline along side of platform.
STEP 7 Make bearers level along their length and with each other. Temporarily support bearers using bricks.
STEP 8 Put first joist between bearers flush with ends, and nail. Continue fixing joists between bearers, spacing them 450mm from centre of 1 joist to centre of next. Finish with a joist flush with other end of bearers.
STEP 9 To support shed walls parallel to joists, install a joist adjacent to outermost joists. Nail offcuts to side of outer joists at each end and in centre of their span. Put a joist against blocks, nail through joist into blocks and through bearers into joist.
STEP 10 Use chalk line to mark across top of joists in middle of their span. Cut blocking to fit between joists and nail in place, staggering blocking to either side of line. Prior to fixing final blocking piece, ensure total width of joists is same as width at bearers. Adjust final block length to suit.
STEP 11 Repeat Steps 8 and 10 to install joists and blocking between middle bearer and bearer at other end of platform.
STEP 12 Slip joist hangers under joists at bearers and nail using timber connector nails. In corners, use multigrip angled brackets to connect joists to bearer.
STEP 13 Measure diagonals of platform, checking for square and level.
STEP 14 Mix concrete in wheelbarrow and pour into post holes. Leave to set.
STEP 15 Use chalk line to mark line across top of joists 90mm from outside of end bearer where shed will sit. Spread construction adhesive along top of joists to attach the first floor sheet. Remove tongue from flooring. Lay flooring on joists so it meets chalked line and is 90mm from outside joists on each side of platform. Predrill and use 50mm screws to fix flooring to joists.
STEP 16 Spread construction adhesive along joists for second floor sheet. Put sheet on joists so tongue is against groove in sheet already laid. To make join tight, put a scrap block of wood against other side of sheet and use sledgehammer to knock it hard against the first sheet. Predrill and screw floor sheet to joists. Repeat to install the third floor sheet, cutting sheet down along its length so it will fit on joists inside of the hobby shed walls.
STEP 17 Use chalk line to mark a line across joists 105mm from edge of flooring. Nail decking to joist so edge meets this line and ends are flush with side joists. Continue laying decking, using 5mm plastic packer as a spacer between boards. Every 5 or so decking boards measure from decking laid to end of deck on both sides and in centre. If measurements are different, slightly adjust gap on subsequent boards until they are the same.
STEP 18 Nail side and end deck skirting boards around deck flush with top of decking boards. Mitre corners where they join.
STEP 19 Apply 1 coat only of decking stain (Mornington Dew) to get a washed look on the timber.
STEP 20 Construct shed following manufacturer’s instructions. On front wall panels, trim cladding at bottom of wall to make flush with bottom plate of wall frame. Fit offcut of flooring into gap at door threshold.
STEP 21 Apply oil-based primer to exterior of shed. Let dry. Apply 2 coats of low-sheen acrylic (Wave quarter-strength) and a stripe (Camisole) around 2 of the boards on shed. Allow to dry after each coat. Paint trim (Wave full-strength).
STEP 22 Cut wall lining sheets to suit side and front walls so joins meet on wall studs. Undercoat all sheets and let dry. Apply 2 coats of interior acrylic (Surf Wash) and chalkboard paint (Zuni) to each wall allowing to dry after each coat. Put sheets against wall frame and nail into framing timbers.
STEP 23 Cut pegboard sheets to fit vertically on the wall with edges meeting over wall studs. Undercoat, let dry, then apply 2 coats of interior acrylic (Iced Vovo), allowing to dry after each coat. Put against wall so short edge is flush with top of wall frame. Fix to wall using 30mm button head screws. Fit offcuts of wall lining in gap between bottom of pegboard and floor of shed.
STEP 24 Vacuum floor, then apply undercoat and let dry. Apply 2 coats of durable exterior acrylic (Timbercolour in White), allowing to dry after each coat.