How to Plan for the Installation of a Drop Ceiling

Before you rush out to the nearest Lowes, though, you’re going to need a plan. You’re going to need to know how to layout the grid to hang your ceiling tiles from, and you’ll need to know how much of each part your layout is going to require.

Let’s take a look at how a drop ceiling is constructed, so you can start developing your plan.

How a Drop Ceiling Works

A drop ceiling is pretty straightforward. It consists of a metal grid suspended from the ceiling and a set of tiles that fit inside that grid.

Sounds simple, right? Not quite.

The metal grid consists of three main parts – wall moulding, main beams, and cross-beams or cross tees.

The wall moulding creates the outer barrier for the ceiling. It is screwed into the wall, and it will hold up the panels along the perimeter of the ceiling.

The main beams create the backbone for the ceiling. They are anchored into joists, and they support the weight of the entire ceiling grid. These beams run perpendicular to the joists in the ceiling, and they should be spaced four feet apart.

The cross tees create smaller sections – generally 2′ x 2′ or 2′ x 4′ – that the ceiling tiles actually fit in. They anchor into the main beams or into other cross beams. If your tiles are 2′ x 4′, you’ll only need to use 4′ cross tees. If you use smaller tiles, you’ll need to use a mix of 2′ and 4′ cross tees.

Creating a Diagram

Now that we know how the grid is constructed, we need to layout how the grid will fit into your room. Graph paper would be immensely helpful here.

Start by outlining the perimeter of your room. Make note of which way the joists run, but don’t draw them on the interior of the room – it’ll add a lot of clutter.

Next, you’ll need to calculate how many main beams you’ll need and draw them on the diagram. These beams need to run perpendicular to the joists. Orient your diagram so that the main beams are running top to bottom, and the joists are running left to right, and determine the width of the room.

The main beams should be spaced out at intervals of four feet. To calculate how many beams you’ll need, divide the width of the room by 4. Ignore the remainder – the whole number is the correct number of beams to use.

For example, let’s assume our room is 15 feet wide. 15 divided by 4 is 3. Therefore, we need three beams. Center these on your diagram, space them four feet apart, and draw them in the length of the room.

Tip: If you have an odd number of beams, place the center beam directly in the center of the room. If you have an even number of beams, draw a dotted line in the center of the room and draw in a beam two feet to the right and to the left of that line.

Finally, you’ll need to sketch in the cross tees.

If you chose to use 2′ x 4′ ceiling tiles, you only need to draw in one type of cross tee. You’ll need to use four foot cross tees to span the gap between each of the main beams and the moulding. These should be centered, and placed at an interval of two feet.

Similar to the main beams, you can use division to figure out how many cross tees you’ll need in each row. Divide the length of the room by two and use the whole number. For example, if our room is 17 feet long, we’ll need 8 cross tees. You should also center these the same way – for an odd number of tees, place the center one along the center line of the room, and for an even number of tees offset them by one foot.

If you are using 2′ x 2′ ceiling tiles, you can begin by drawing in the 2′ x 4′ cross tees. However, you’ll need to add a second set of tees. You’ll notice that the 2′ x 4′ cross tees create areas that are too big your tiles – in fact, they are the perfect size for 2 of your tile. Place a 2′ x 2′ cross tee in each rectangle on your diagram.

Estimate the Materials and Cost

With diagram in hand, you’re ready to go purchase your materials and start hanging. Either count up the number of each piece in your diagram, or figure out some fancy math to make it simpler. A bit of simple multiplication and division should do the trick.

To estimate the cost of the project, you’ll need to know how much of each of the following you’ll need:

Moulding (length in feet)

Main Beams (# of 8′ or 12′ pieces)

2′ x 4′ Cross Tees

2′ x 2′ Cross Tee (if applicable)

Ceiling Tiles

One last tip. If you’re lazy, and don’t feel like sketching out the diagram by hand, you can cheat. Armstrong, a suspended ceiling manufacturer, offers a free tool on their website to diagram and estimate materials.

Disappointed that you did all that work, when a computer could have done it for you? Don’t be. The better you understand how a drop ceiling goes together and how each of the components fits into the whole, the easier it will be for you to complete the project.