Certain types of DIY work require detailed measurements - sometimes a whole series of them. Traditionally, the tape measure with the aid of a pen and paper, were the go-to tools to complete a measuring task. However, in today's modern digital world, the laser measure, this time in conjunction with a mobile device, are becoming more common.
As its name suggests, a laser measure, also known as a laser distance meter or laser distance measurer, is a small handheld device that uses laser light to measure distance. The laser measure works by directing the laser light to reflect off a distal surface back to the device. This allows the laser measure to calculate the distance to the distal surface using the time it takes for the light to make the round trip.
Laser measures are typically used to measure distances between walls, ceilings, and floors. However, they can also be used to measure lengths of almost any physical structures around the home like window frames and cabinets. Most devices can also use these measured distances to calculate areas and volumes of the rooms or defined spaces. Laser distance meters have outdoor applications as well, such as measuring distances and areas for fencing and landscaping. As a result of this versatility, laser measures are now increasingly used in a variety of industries including construction, architecture, interior design, and real estate. However, their use by the tradesperson and the humble home DIYer are becoming increasingly common too.
Laser measure vs tape measure
So why use a laser measure when a tape measure will suffice? Well, first of all, there is nothing wrong with using a tape measure. In fact, in some situations, especially where there is no easy surface to reflect a laser off, a tape measure would be the better tool. However, in other situations, like measuring between parallel surfaces, or over long distances, a laser measure is going to be superior. A laser-based measuring device has a number of advantages over the traditional way of doing things. These include:
Features to look at when buying a laser measure
Laser measures, like other laser tools, typically use a red laser as their light source. This is because red light is more readily available and less expensive than other laser colours. However, there are some laser measures that employ a green laser instead of the standard red one. Green lasers have the advantage of being more visible in bright conditions and at longer distances which can make it easier when aiming them. Green lasers, however, are more expensive and require more power to operate which can have a negative effect on battery life. Ultimately, the choice of laser colour will depend on the specific needs and preferences of the user and the conditions in which the laser measure is to be used.
Red Lasers vs Green Lasers in Laser Measures
(especially outside & at a distance)
Lots of device models to choose from
Fewer device models to choose from
Marginally less expensive
Marginally more expensive
Uses less power
Uses more power
Another key feature to look into when purchasing a laser distance measurer is its measurement range. This refers to both the minimum and maximum distances the device can measure accurately. Laser measure range typically goes from a few centimetres, at the low end, to tens of metres when measuring greater distances. Laser measures with an upper end of the range between 30m and 50m are usually more than sufficient for most, if not all, trade and DIY work. However, some outdoor practitioners will benefit from laser measures that can measure distances up to 100m or more. Measurement range, therefore, should be one of the specifications to assess when choosing a laser measure in order to ensure its range matches your requirements.
Another specification to be aware of when buying a laser measure is its accuracy. Most laser measures have an accuracy of around ±1.5 millimeters, which is more than sufficient for most trade and DIY applications. However, it should be noted that, to get this level of accuracy, the measuring device needs to be steadied against a stable surface or used atop a tripod.
If accuracy is even more critical, then some very advanced laser distance meter models can achieve accuracies of up to ±1.0 millimeters. However, such meters are more expensive and are usually overkill for most DIY and trade jobs.
Laser measures with internal memory are designed to store and recall previous measurements for added convenience and efficiency. This memory feature allows users to save several measurements, which can be useful for complex projects that require multiple measurements of distance, length, area or volume. Some laser measures also have the ability to add notes or labels to each saved measurement.
Memory functions on a laser measure can help reduce errors and improve accuracy by relieving users of the need to remember results and allowing them to quickly cross-check previous measurements. This can save time and effort for users, and therefore, is yet another important feature to take into account when choosing a new laser distance meter for the tool box.
It is probably no surprise that laser measures are powered by batteries. The type and number of batteries used by the devices can affect their performance, runtime, and convenience of use. The vast majority of laser measures use standard AAA or AA alkaline batteries, which are widely available and easy to replace. However, these types of batteries tend to run down quickly especially in devices that have higher-end features such as colour screens or more powerful lasers. As a result, using such disposable batteries will add a recurring additional cost both to the pocket and to the environment.
Some high-end laser measure models use rechargeable Lithium-ion (Li-ion) battery packs, which can be more convenient and economical to use. Laser distance meters with Li-ion batteries will usually have a USB-C port, allowing them to be recharged from almost anywhere there is a USB outlet. This type of rechargeable battery is especially convenient for users who make frequent use of their laser measures and don't want to deal with the hassle of regularly replacing batteries. Li-ion batteries will also typically run at marginally higher voltages than with standard batteries. This allows these devices to support higher-power lasers with greater measurement ranges.
Dust and Splash Protection
Laser measures are often used in harsh environments like construction sites exposing them to substances with the potential to damage them. As a result, many of the devices are designed to resist dust and liquid ingress to various degrees. The level of protection is quantified using the Ingress Protection (IP) rating system, which gives an indication of just how resistant a device is to dust and water ingress. The first 'x' or number in the 'IPxx' code refers to the level of ingress protection from solid objects of various-sized diameters (ø). The second number (the second 'x' in the IPxx code) codes for the level of protection a device has against the ingress of water.
Ingress Protection Code (IPxx)
(ø = diameter)
Protection against of objects
≥ 50 mm ø
vertically falling water drops
Protection against of objects
≥ 12.5 mm ø
vertically falling water drops when device tilted up to 15º
Protection against of objects
≥ 2.5 mm ø
Protection against of objects
≥ 1 mm ø
powerful water jets
temporary immersion in water
continuous immersion in water
high pressure and temperature water jets
An IP rating of at least IP54 (i.e. protected against dust & splashing water) is the minimum recommendation for laser measures that are going to be used in harsh environments. However, even for home DIY, the more protection a laser measure has, the better. Fortunately, the vast majority of laser distance meters have been built to at least the IP54 standard, so this level of protection should not be hard to find.
Irrespective of the protection level, it is still important to handle laser distance meters carefully and to follow any manufacturer usage recommendations. This will ensure that the device stays calibrated correctly and has a long life.
Laser measures are generally lightweight devices making them easy to carry around in a pocket or tool belt. However, the weight of a laser measure can vary depending on the features it offers. Most devices weigh between 80g and a couple of hundred grams or so. The heavier models will usually have advanced features such as built-in digital viewfinders and larger more capable displays. Therefore, when choosing a laser measure, it's important to consider a device's overall weight (including installed batteries) and how portable it will need to be. Lighter laser measures will be more comfortable to carry around - important if you have to work in a lot of different locations - while heavier devices will be more stable and offer more features. Ultimately, the weight of the laser measure chosen will depend on personal preference and specific needs.
When it comes to laser measures, if you just have to make the odd measurement now and then, then a simple device without wireless connectivity will more than suffice. However, if you envisage having to make a whole series of measurements in one go or if the measurements need to be shared or imported into other software, then a laser measure with the ability to transfer those measurements automatically to a smartphone or tablet may be more appropriate.
To this end, a number of laser measure models come with Bluetooth connectivity which allows them to connect, and automatically send any measurements made, to a mobile device app. This can significantly streamline one's workflow as it obviates the need for having to write down or input measurements manually.
Hand-in-hand with this wireless connection usually comes the ability to do more advanced operations, such as to automatically add measurements to a photo of the workspace, or to create complete floor plans. Importantly, however, a device's Bluetooth capabilities will also heavily depend on the accompanying mobile app provided by the manufacturer. Therefore, when selecting a laser measure for its ability to connect to a mobile device, it is also important to investigate the features of the associated application software as well.
What might I be able to do with a laser measure's Bluetooth connection?
Record a long series of measurements automatically
Annotate measurements on a photo of the workspace
Streamline the making of floor plans of rooms and buildings
Aside from their basic distance-measuring functions, higher-end laser measures also possess some advanced features. These features can include:
Digital Spirit Levels / Tilt Sensors
Unlike the bubble spirit level, digital spirit levels employ electronic sensors to determine if a structure or surface is level. Using a digital spirit level is easier and potentially more accurate than the traditional method. Having a spirit level on a laser measure also makes its primary function of distance measurement more accurate as the user can ensure that horizontal and vertical measured distances are perfectly square to the horizon.
Inclinometers / Angle Finders
Using the same technology as the digital spirit level, some laser measures also feature an inclinometer as part of their design. Similar to the spirit level, the inclinometer gives the laser measure the ability to find the angle of a surface, which can be useful in a variety of building and DIY situations. For example, measuring the slope of a roof or staircase under construction can help ensure that the materials used to build them are cut to the correct angles. The inclinometer also plays a role in the making of indirect measurements by participating in a feature that is often called Pythagoras Mode (see next section).
Indirect Height, Length & Surface Measurements (Pythagoras Mode)
Some laser measures feature what is often referred to as Pythagoras Mode or Pythagoras Function. This mode allows the laser distance meter to be used to make indirect height, length, and surface 'measurements', which can be especially useful when direct measurements are difficult or impossible. Typical examples include the measuring of the height of a tall building, determining the surface area of part of a large wall, or measuring the distance between two points separated by an obstacle.
For example, for an indirect height measurement, two distances from the laser measure have to be measured (red dotted lines in the first picture above), one of which being directly perpendicular to the height under determination. The device can then automatically calculate the height by employing the Pythagorean theorem on the right-angled triangle that is formed.
Alternatively, to make an indirect length measurement, the laser measure is used to determine the distance to each end of the structure being measured. The angle of elevation is also retrieved and together they are used to calculate the indirect length between the two measured endpoints.
Using these indirect measuring methods, users can make measurements of height, length, and surface area with good levels of accuracy. Indirect measurements are common in construction and engineering but can also be useful in some challenging DIY projects.
Some higher-end laser measures have colour displays which can enhance the user experience with their more aesthetic appearance. A colour display can also make it easier to use the laser distance meter in low light or when visibility is poor, as its backlight will ensure the information is clearly visible.
Digital Viewfinders & Zoom (Point Finder)
Some top-end laser measures have digital viewfinders with zoom capabilities, which are useful features for longer distance measurements. Unlike a standard laser measure, which must be lined up with the target point unaided, a laser measure with a digital viewfinder employs a small camera on the device to display an image of the target area. Using this digital viewfinder, users can then see where the laser is actually pointed and make any necessary adjustments.
Most digital viewfinders on laser measures will also be able to zoom allowing operators to get an even closer look at the target area. This is especially useful when measuring distances further away or aiming at more challenging locations where the laser dot is not clearly visible with the naked eye. A typical example is measuring the distance to the top of a building when standing some distance away from it. This would typically make it difficult to see exactly where the laser is pointed. With zoom on a viewfinder, users can see the top of the structure in more detail and place the laser at its very top more precisely.
Flip-out End Pieces For Corner Measurements
Finally, flip-out or fold-out end pieces are also special features found on some laser measures. These end pieces usually consist of a plastic structure that can be physically extended outwards to make measuring from diagonal corner or outside corner edges easier and more accurate. For example, when checking the squareness of a window frame, a straight flip-out end piece can be extended from the laser measure to get right into the frame's corner to measure the distance to the diagonally-opposed edge. Similarly, when measuring the distance from the outside edge of a wall or other structure, a right-angled end piece can be used to hook onto the outside corner edge and provide a more accurate measurement from that location.
Popular Laser Distance Measures in the UK
** Weight includes battery
†† Rechargeable battery pack available as an optional accessory
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