What We Cover in This Article:
- First Determine your Box Mounting Heights
- Always Consider Drywall Depth (Being in is Better than Out)
- Does the Layout Make Sense?
- Recommended Boxing Tips for an Awesome Workflow
First Determine Your Box Mounting Heights
Even before you consider installing a box while you’re in the rough-in stage, it’s absolutely crucial to know your mounting heights.
It’s crazy how many times I’ve had to go back because a foreman got the mounting heights wrong.
This really eats up time on a job fixing simple tasks like this.
So know your numbers!
In a condo, for example, we’d have to know heights for:
- Kitchen Counter Plugs
- Fridge Plug
- Fire Alarm Devices
- Emergency Heads (Remote Heads)
In addition to mounting heights, you also have to be aware of your ceiling heights, too, as you don’t want devices above the ceiling or too close to the ceiling!
And, besides heights, we also have to know of any special rules.
A common special rule would be party walls, for example! (A party wall is a wall that is shared with a separate suite. Boxes typically have to be a full stud-space apart and cannot be a data ring – a single-gang box must be installed instead. Party walls are in shared-unit buildings.)
Trust me, it’s important to get all these details up front. Otherwise, I guarantee you’re going to waste time going back and tweaking these simple tasks!
Where to Find This Info:
So, where do we find these mounting heights and any special rules pertaining to our building?
The site specs are that particular job site’s guidelines on how the engineer wants the job done. (Don’t let those slip through the cracks. It’s really important stuff – it can be the difference between a pass and fail through your inspection/walkthroughs.)
Plywood Floors in Condos – Poured Concrete Adds 1.5″:
Another super important tip about mounting heights in condos is when you are on a plywood floor.
For example, your first floor is the actual concrete slab, so your mounting heights are exactly as they are told to you on the site specs.
But, once you go up a floor in a wood framed condo, you are then walking on a plywood floor which eventually gets poured with 1.5″ liquid concrete! (If you don’t take this into account, all your devices will be 1.5″ too low!)
How this works is the framers install two bottom plates on the floors above the main concrete slab.
When they pour the liquid concrete (called gyp-crete), they pour it just enough to cover the first 2x4, which is 1.5″.
So on the floors above the main concrete slab which are just plywood during your rough-in stage, you have to add 1.5 inches onto the given measurements, as the prints typically say A.F.F. which stands for Above Finished Floor.
The plywood floor is not your finished floor, the poured concrete is!
Not adding 1.5″ to your mounting heights before concrete is poured on your upper floors is a rookie mistake to make!
Always Consider Drywall Depth (Being in is Better than Out)
The next thing you want to consider is your drywall depth.
Especially when working in condos, we can deal with 1/2″, 5/8″, or multiple layers of drywall. (Sometimes soundbar is also included which adds even more depth.)
What this means is you have to break off the tabs on your box so you can stick the box out to the correct depth.
Now, in my experience, it’s ALWAYS BETTER TO BE TOO FAR IN than too far out.
There is a code rule that specifies how far you’re allowed to be in the drywall, but you can easily use a box extender so you can comply with these rules.
When a box is too far out you have to cut down the plastic to make it flush with the drywall. Otherwise, when you install your device, your cover plate will have a noticeable gap in it! (This is a horrible fix to have to make.)
So where do you find this information on drywall depth?
You’d find drywall depth info on the architectural prints.
There’s usually a page which shows you all the different types of walls/ceilings and what each wall/ceiling gets. It tells you exactly from start to finish that exact materials used.
For example, let’s say our wall designation is P2:
- Finished Paint Color
- 1 Layer 5/8″ (Suite Side)
- 2x6 Roxull Insulation
- 2 Layers 5/8″ Drywall (Corridor/Hallway)
- Finished Paint Color
So wherever you’d see the P2 designation, you’d know what side gets 2 layers of 5/8″ drywall and what side only gets 1 layer.
It’s tricky to keep track of drywall depths, so sometimes you can use spray paint studs to determine drywall depth ahead of time, or just simply write on the stud to save yourself from always checking.
Don’t forget about your ceiling drywall depth, too. Especially in a condo, these drywall depths can change, like if you were on the top floor compared to the first floor for example.
Does the Layout Make Sense?
This one will happen with experience, but over your years you’ll pick up the common tricks for laying out boxes and if the layout has an error or is kind of funky feeling.
- Are the plugs all within 12′ and on usable wall space?
- Do the 3-way switches make sense?
- Do the prints show the panel in a closet? (Not allowed!)
Recommended Boxing Tips for an Awesome Workflow
So if you’re ever in charge of apprentices or left alone, here’s my recommended tips to you when you’re on a brand-new job site and now it’s time to start boxing!
- Find your mounting heights first – I’d also suggest to cut templates out of wood. For example, cut a piece of wood at your switch height and a piece of wood for your plug height to save time. If your boss doesn’t like that then I guess you’re going to have to use a tape measure. Make sure to cut new template sticks when you move up to floors that require you to add 1.5″ because the concrete is not poured yet, or you’re devices will all be 1.5″ too low!)
- Walk around the rooms with prints and draw symbols on the studs where devices go and mark the heights, too!
- Layout all your boxes underneath the studs, making sure the outside boxes are vapor barrier boxes.
- Cut and layout scabs for boxes where they should be out 1 or two stud spaces. (To get away from the door frame trim, if a box is three gang or larger, or if it’s too close to another box, for example.)
- Load up on 1″ screws for your boxes and long screws for your scabs (Sometimes a company will use nails instead of long screws for scabs. Nails are less expensive, but screws are definitely faster.)
- Grab your drill and have at it!
This is by far the fastest way I’ve found to box out a suite in a condo or home.
Hope your boxing improves 😉