How to guide- Plan and Lay a Deck

Published On: 09/03/2021Categories: How To Guides

Planning and Preparation- the method on this guide is based on installing a single level deck with a timber frame and horizontal deck board positioning. Different decking designs may require different techniques and spacing
Start by deciding the location, bearing in mind factors such as privacy and sunlight. Heavily shaded areas may require more maintenance, and damp areas should be avoided. If building next to a house make sure its 150mm below the damp proof course, and that you don’t cover any airbricks.
Carefully plan your deck before starting, factoring in gaps or 5-8mm between the deck boards in order to limit cutting and wastage, saving money when ordering. Ensure the fall of the frame is 1:100 and running away from the house.

Doing it Right- use two coats of preservative to treat all drill holes and cut surfaces
When sawing use the 90 degree guide marker/ a set square to help ensure accuracy
Sand cut ends of timber

Staying safe- firmly secure the timber when sawing or drilling, when drilling use safety goggles
Wear protective gloves when applying wood preserver or handling the deck boards
Wear a dust mask when sanding down any rough edges-cuts of wood

Aftercare- Once completed apply a decking stain to protect the timber, if in a shady spot its recommended to clean and treat the timber annually, and to keep it clean just brush it.

Preparing the area
Step 1- An existing patio or concrete base can be used as a foundation for your deck. Start by measuring and mqarking the decking area out.
Step 2- If laying on lawn, mark out the area and dig out a depth of 50mm. Cover the ground with landscaping fabric and add gravel and if the ground if soft we recommend adding paving stones on top of the gravel.

If you are building a deck fixed to a house, read below, if it’s a free standing deck, skip to the ‘Assembling the frame’ section
Adding a wall plate
Step 1- Make a vertical line where the end of the wall plate will be against
Step 2- If planning around a step or sill, check the design fits by taking an offcut of deck board and placing it under the lowest part of the sill making a small line underneath it, using that line, drop the board down by 10mm to allow for any expansion, using a spirit level draw a level line, if possible extend this line across the full width of the decking.
Step 3- cut the joist to length
Step 4- Measure 100m in from one end and mark the wood, draw a vertical line down from your mark
Step 5- Measure 50mm down from the top of the line, and 50mm up from the bottom, and mark the wood. This will indicate where the pilot holes will be drilled.
Step 6- repeat this process at 600mm intervals, at the end of the wood mark out another 100mm section
Step 7- drill the pilot holes using a 6mm drill bit
Step 8- Put the wall plate into position in line with the guideline you drew in step 2, check it is level
Step 9- check the deck board still fits under sill
Step 10- drill guide holes into the wall using a 7mm masonry drill bit, you may need to ask someone to hold the timber in place for you whilst you do this
Step 11- Move the plate away and complete the holes by drilling into the wall
Step 12- Put wall plugs into the drilled holes, use a hammer to push them into place if needed
Step 13- insert 6mm x 100mm screws through the holes in the wall plate, hang plastic or galvanised washers on the end to ensure a 10mm gap between the wall and the plate
Step 14-Hand tighten the screws into the wall plugs and then use a drill and driver bit.

Assembling the Frame
Step 1- If your decking is going to be longer than the decking joists, you will need to join two sections together. If you don’t need to join your joists, move them into position and go to step 6
Step 2- Start by measuring and cutting the section you need to reach the required length for your joists
Step 3- measure and cut a 600mm section and mark at 300mm-centre point. Secure the sections in your workbench or saw horse, ensuring the 300mm mark lines join in the joists
Step 4- Measure 75mm from each side of the join and mark. Then measure 150mm and repeat. Draw a straight vertical line from the four marks
Step 5- mark two evenly spaces pilot holes on each line, drill pilot holes using a 6mm wood drill bit, secure with 100mm screws
Step 6- Frames need to be at the required level before fixing, use rises, paving slabs or offcuts pf timber at 500mm intervals, check with a spirit level, check the corners are square.
Step 7- To join the frame, mark and drill pilot holes before fixing two external grade 150mm timber drive screws into each corner,

Adding Internal Joists
Step 1- To work out how many are needed, measure 400mm from the centre of the external joists, mark it, measure from this mark and repeat at 400mm intervals.
Step 2- If you need to extend your internal joists, follow the same method you did to join the external joists, but with the addition of an extra 600mm section on the opposite side to sandwich the joist in place. Make sure to offset the bolts
Step 3- Secure the joist in your workbench and attach a joist hanger to each end using 30mm exterior screws
Step 4- Place the joist into position, with the centre lining up with the 400mm spacer mark, joist needs to be flush with the exterior frame
Step 5-Extend your 400mm guide marker down the external face. Using this line measure 40mm up from the bottom and 40mm down from the top, mark two pilot hole guides, and drill the pilot holes using a 6mm drill bit
Step 6- Drill countersink holes and secure with 100mm timber drive screws, and repeat for the rest of the joists
Step 7- for unexposed sides of the frame, drill two skewed pilot holes on each side before securing
Step 8- Add the final 30mm screws to each joist hanger

Adding Noggings
Step 1-Measure out and prepare enough noggins so that the distance between them will never be greater than 1200mm, best to stagger the noggins
Step 2- Add packers if necessary. Draw a line down the centre on the noggins position on both of the joists it will join to, measure and mark pilot hole guides 40mm from the bottom and top on each side, drill the pilot holes, secure with 100mm external timber drive screws

Laying the Deck Boards
Step 1- its best to predrill all holes with a 2mm bit to prevent damage or splitting
Step 2- screw into the second groove from each side and fix to the frame with 64mm decking screws, repeat at the opposite end of the board, then work down the board, fixing the screws into each joist
Step 3- to ensure a 5-8mm gap between each board create a suitable sized spacer using an offcut of timber, use it to check the gap all the way along

 

For our decking click here

 

Share this story