3 Steps to Measure a Room or House for Square Footage and Perimeter

Is it difficult to measure a room or house for the area and perimeter? Not at all. Homeowners can easily do that measurement at home with very easy-to-grab and cheap tools

In this post, you will find three easy steps to measure the square footage and perimeter. Whether it's for renovation, furniture purchase or rearrangement, walling with paint or wallpapers, or flooring, check the content below and get the exact data.

What do we need to measure a room or house

There's no way you can measure a room and get the exact data with just eyes and hands. We need some tools for the measurement.

1. Measuring tool

To measure a room or house, a measuring tool is 100% necessary.

If it's just a small room, a regular 5-meter or 16-feet tape measure is fair enough.

Tape Mesure Tool

For a big house, a tape measure may cause a big error. An upgraded measuring tool is required for an accurate measurement, a laser measure.

Tip: What is a laser measure

This is an advanced and precise tool. Similar to radar, it emits infrared lights to objects and analyzes the reflection. And finally, calculate the distance from the laser lens to the target objects.

Laser Measure for Room

Compared to a traditional tape ruler, this laser tool is more accurate as it requires fewer manual steps. Also, it's easy to use. Just point the infrared lens to the wall or floor, a laser tape will give you the exact data in no time.

Though a laser model is slightly expensive, it's still acceptable. You can get a laser measurement device at around $20 like the famous NOYAFA NF-271L. Just $10 higher than the tape ruler.

Bonus: Laser and tape measure combo

Both tape measure and laser measure have their advantages. Some manufacturers know this and release combo, laser tape measures.

This ultimate measuring tool is installed with an infrared emitter and receiver as well as a tape ruler. When it's a big house, turn on the laser mode. For easy measure, pull out the ruler.

If you're interested, check on NOYAFA's NF-2240 Laser Tape Measure. This is an affordable and easy-to-use laser measuring tape. 

Of course, there're more on Home Depot, Amazon, Costco, and local hardware stores.

2. Markers

If you're using a tape ruler, you will need a pencil or marker pen to help you draw some lines or dots. This will make the measurement more convenient and fast. Also, it helps you measuret in a straight line.

3. Pen and paper

You do need something to note down the data. It's easy to forget things especially numbers with decimals.

So, ready a pen and some paper. Write down the numbers every time you finish measuring a wall or floor.

4. Helper

Is there anybody there to help? If there is, your measurement will be easier. He/she can hold the tape ruler firmly attached to the wall or floor.

No one to help? Well, get a laser measure.

Part 2: How to meausre a room or house

All ready! Let's start to measure your room or house.

Step 1: Measure the length, weight, and height of a room

When you're using a tape ruler:

Locate a wall and clear the obstacles like curtains and hangings.

Tip: We'd better measure a wall that has windows. The window sill will help us measure in a horizontally straight line.

Start to measure the length (one of the longest wall) with the tape ruler.

If there is a hook attached to the ruler, it may cause inaccuracy. You can just flip the blade back. Let the hook side face you and the side with numbers to the wall.

Slowly drag the case to the other end of the wall. Keep the blade horizontally straight. You may use a stick or other objects as a helper.

Use a pencil or marker to leave a mark on the blade. Read the number and write it down on the paper.

Recoil the tape measure and measure the width (a shorter wall).

To measure the height, start from the corner formed by two walls. Use it as a helpful to make the blade vertically straight.

You will use a ladder to measure from the top of the corner to the bottom.


For a coboid room, you just need to measure the length, width, and height.

But if it's a trapezoid or triangle room, you need to measure all walls.

When you're using a laser measure:

As for a laser measure, things get easier.

Place the device against the wall and floor. Press the measure button to get the data.

You may write the numbers down. Or some laser measuring tools like NOYAFA has a local storage to save these data.


Laser measures are designed to measure the distance from the infrared lens to the target object. But the the length or height of the tool will be added to the final displayed result. So, don't worry about the result will be shorten.

Step 2: Calculate the perimeter

It's pretty easy to calculate the perimenter of a room. Simply plus the length and width together. 

For a laser measure like NOYAFA NF-271 and NF-274L supports auto-calculate. Simply boot the tool to  mode. It will do the math for you.

Step 3: Calculate the square footage

  • Floor & Ceiling: Multify the length and width together.
  • The square footage of the longer wall: Multify the length and height
  • The shorter wall: Multify the width and height
  • Total: Add them up

For laser measures, they will do the area measurement automatically. Simply boot them into the correct mode. Measure the lengths of two sides. Leave the rest to the machine.