🖼️
The project:
I cut out a section of the existing balustrade on our balcony, and installed steps complete with matching balustrade in merbau.
I found the main challenge to be trying to source timber with dimensions that match our existing balustrade. I had to use merbau / hardwood due to our BAL rating.
- Materials:
For the Balustrade (this is mostly a copy and paste from my shopping list):
90 x 90mm 2.4m Post GL17 Pre-Oiled Merbau DAR I/N 0549667, cut at 1270mm
42*42 2.7m merbau screening. For bottom rail. (I/N 0517074)
42*19 2.7m solid screening (I/N 0517078) for top screw in strip
90*42mm 5.4m PR4 Beam for the handrail I/N0549670 (cut at 1.2m, 2.7m)
Merbau pickets / uprights / screening 65*16mm (not available from Bunnings)
2x Dunnings 160*35mm M10 gal brackets I/N 1076781
VUEPRO 90-110mm M10 Concealed Thread Bolt - 2 Pack, I/N: 0182342
125mm M12 gal bolt and washer x1
Decking screws Titan 10g*50mm treated pine screw 100? I/N 0658853
Cabots Aquadeck Natural Exterior Decking Oil
For the steps:
Dunnings 75 x 50 x 5 x 190mm M12 Structural Angle Bracket x2 (I/N 1070445)
M12 hot dipped galv bolts with washers x4
Ramset 12 x 75mm Galvanised AnkaScrew Masonry Anchor I/N: 2260292, x4
125mm construction screws and various other screws
For the concrete slab:
Dingo 20kg Hi Strength Concrete (I/N: 0760378) - you don't really need high strength, but the price difference per bag isn't that great and I usually like to over-engineer my stuff
STRUCTAply 1200 x 595 x 17mm F14 Plywood Formwork (I/N: 0390167) - I tend to wash these up after use and reuse them for various projects
Fibreglass rebar - I got them from Bunnings which has unfortunately stopped selling them, but you can still buy them from Mitre10.
- Tools:
Cobalt drill bits 3mm, 10mm, 12mm (since I was using hardwood, less durable drill bits would snap pretty easily)
12mm masonry drill bit
255mm compound mitre saw
Drill and drill bits (A couple of years ago I got this Ryobi 18V ONE+ 4 Piece Kit R18X4C1422B I/N: 0539762)
F clamps
Plunge router and router bits
Spirit levels - different sizes
Measuring tape
300mm Combination Square
Pencil
Sander and sand paper
Ratchet Socket Set
For the concrete slab:
Steel wheelbarrow and various tools for mixing and leveling / finishing concrete such as a concrete trowel
Safety gear:
Earmuffs
Safety goggles
Dust masks (esp for mixing concrete)
- Step 1:
Plan, seek advice, and read up on the NCC (national construction code) and any local council regulations.
My main source of advice came from my dad, who had built shops, houses, sheds and a shack over his lifetime.
I read the NCC in detail to ensure the new steps and balustrade were compliant, including height requirements, max gap allowed, etc.
The photo below is a slightly outdated "before" pic, before we got the grass and the garden beds, since I didn't exactly take a "before" photo right before the start of the project.
- Step 2:
Do measurements and source materials.
At this stage the main measurement was the height from the ground to the top of the existing alfresco. This is complicated by the fact that we will be building a deck afterwards.
I went online to get a couple of quotes for decking kits - kits that come with composite deck boards, and aluminium subframe. After deciding which quote I was going to go with, I checked the minimum height of that particular system (eg 100mm from ground). This would become the level that my staircase would descend onto.
I had the option of the stairs sitting atop the new deck, with further reinforcement built into the subframe. But I eventually decided against this due to vairous disadvantages such as being unable to replace deckboards without removing the staircase.
I went online to find pre-made outdoor staircases. I was going to get the "Peak Products Black 7 Tread Steel Stair Stringer (I/N: 0396486) from Bunnings. But the 7 tread version was just like 150mm too short in terms of height; and to get 8 treads, you had to buy 2x 4 tread stringers plus a joiner, with the joiner itself to be supported from the ground.
I ended up buying a "flatpack" 8 tread merbau stair kit from the mainland which was the perfect height. The kit came with 2 stringers (with grooves for the treads pre-cut), all screws for the treads, and the treads.
- Step 3:
Concrete Slab
While waiting for the delivery of the stair kit, it was time to buy too many bags of concrete and start concreting.
Part of the concrete slab would be resting on part of our house footing. That part was about 200mm thick. As the land sloped away from the house, the thickest part of the slab was about 400mm.
As you can see from the photo, the slab has been split into 2 halves, at least at the top. That's because initially I was planning to save some concrete and had the concrete step down The plan was to use a stirup post anchor to support the stringer on the lower side. But at the end, I decided against that, so I poured another slab on top of the previous slab, but not before drilling 5 holes into the previous slab, filling them with chemset, and inserting rebars into them. So the "new new" slab was secured onto the "new" slab by 3 rebars at the bottom and 2 rebars on the side, all of which secured by chemset.
- Step 4:
Install the stairs
The staircase didn't come with any instructions, so I used 2x Dunnings 75 x 50 x 5 x 190mm M12 Structural Angle Brackets to bolt the stringers to the concrete block using M12 Ankascrews (I drew my idea from the installation instructions for the Peak steel stringers). The stringers were bolted onto the structural brackets using hot dipped galv M12 bolts, washers and nuts, and also onto the existing deck via 125mm long construction screws (this was mostly to stop lateral movements).
Since we have a toddler (about 16 months old then), I decided to install the stairs first without removing the section of balustrade on the existing deck.
And yes, our toddler was at a clingy stage where it was like the end of the world simply because I wasn't around to play with him, despite his mum / my partner being there for him. As a result, I managed to get all of the drilling etc done (the noisy part) during the day, and left some quiet parts to be done in the dark once our toddler was in bed. Hence the photo taken in the dark.
- Step 5:
Cut the existing balustrade
To cut the exsiting balustrade, I had to basically take apart the entire section of it, use a compound mitre saw to make precision cuts, and put the pieces back together. I used some of the PR4 Beam to "finish off" that section of the balustrade, as shown below (it was sunset, hence the pink tinge).
Please note the photo below was after my first attempt, when I didn't really think about it, and ended up screwing the handrail into the new piece of timber from the top. I have since redone it so that the screws were on the vertical part, less visible and you won't run your hands over them.
- Step 6:
Install the new balustrade
As mentioned above, the most challenging part of this project was trying to source the hardwood in dimensions that match our new house's existing balustrade.
For this part, I did my planning in minute details, and extensively utilised the instore cutting service at Bunnings (details as shown on my list of materials above). Having them precut (I always allow at least 100mm of leeway for each cut) also made it easy to transport them in an SUV without a trailer.
First I marked out and used a compound mitre saw to cut out parts of the merbau posts so the stair stringers sat neatly "in" them. I used concealed tread bolts to bolt them to the stringers to make it neater (and so you won't accidentally hit the bolts with your toes).
Then I used my plunge router to route out a notch under the merbau handrail, so I can embed the galv plates into it.
I then bolted the 2 galv plates onto the posts, put the handrail on top, and bolted the plates to the handrail from the underside. As a result, there were no unsightly screws to be seen on the handrail.
Both the handrail (the 90*42mm 5.4m PR4 Beam) and the bottom rail (the 42*42 2.7m merbau screening) were a bit warped / bent, although they were the best ones I could find at Bunnings.
I installed the handrail so that it was "bulging" upwards, I then used a ratchet strap to pull it downwards so that it was as straight as possible.
I installed the bottom rail so that it was "bulging" downwards, and I used bits of timber offcuts to wedge between it and the stringer, so that it was mostly straight.
I then installed a strip of timber under the handrail, to which the pickets or uprights would be screwed into.
Last step was to install the pickets. Note that the picket right in the middle was longer and screwed into the stringer itself for extra support; this would also ensure both the top and bottom rails stayed straight once I removed the ratchet strap and the wedge of timber.
And then I used a 125mm construction screw to secure the top of the new handrail into the exisitng balustrade, to brace everything together
Some things to note:
- Since I was using hardwood. every single hole had to be pre-drilled and counter sunk. I have snapped a couple of screws due to the predrilling not being deep enough.
- Ideally you would let merbau timber weather for a bit before "sealing" or staining it. However, I applied two coats of Aquadeck onto parts of the timber where I won't be able to reach once the whole thing had been put together (eg joints etc).
- For the bottom of the merbau stringers and the timber post that's touching the concrete slab, I applied 2 coats of Aquadeck, and then 3 coats of Crommelin Exterior Grade Brushable Waterproofer. Our builder also left some dampcourse plastic behind, so I cut up some of them to fit under the timber post and the stringers as well for good measure.
- You can see some brown stain on the concrete slab under the stairs. This was the tanin from the fresh merbau. The slab will be mostly covered by our future new deck, so I am not concerned.
- The silver plates holding the bottom rails to the timber posts will be spraypainted to match the colour of the existing steel posts.
- The steel post near the wall will be cut down to near the stringer, and capped - the cap will be colour matched via spray painting. Once the steel post has been cut, I will take it to the local Bunnings store to confirm colour (I am suspecting it's Monument).
- Concrete slab was first poured mid-Feb this year, the final touches to the entire project was completed in July. So between work, early parenthood, and being a volunteer firefighter, this has taken me almost 5 months to complete.
