There are several factors to consider when choosing carpet underlay, such as the use of the room, budget, room size, durability, longevity and comfort. Underlay determines how your carpet will look and feel, and each type of underlay offers a different experience for the end-user.
So generally speaking 7mm is about as thin as you want to go unless you have a specialist need for something thinner, but 8-12mm is the band most manufacturers produce carpet underlay with and its perfect for any room and any carpet.
With that being said, most underlayments are 2-3mm thick, but are sometimes thicker for carpet or to smooth out an uneven subfloor. It's often advertised that 6mm underlayment offers double the sound absorption as 3mm underlayment.
A high-quality PU foam underlay is an excellent choice, as it offers superior cushioning, creating a soft and luxurious feel underfoot. It also provides brilliant insulation, keeping your living room warm and comfortable, especially during colder months.
A 3mm underlay is ideal for flooring less than 18mm thick. This thinner option provides sufficient support without adding unnecessary height. For flooring that is 18mm or thicker, you'll need a 5mm underlay. This added thickness ensures better stability and cushioning for heavier or more robust flooring options.
Choosing a thick (10mm+) underlay for your stairs is not a good idea as it can pose a trip hazard. Moreover, thicker carpet underlays tend to compress slightly with heavy use, which can lead to irregular wear and unsightly lumps, particularly in frequently trodden areas.
If your roof does not have a steep pitch, you can use #15. This weight of felt is a good economic choice if you have a standard roof. But if your roof has a steep pitch, #30 is a better option because it is thicker and tears less during installation. With #30 you get a thicker layer of underlayment and protection.
For traditional plywood flooring installations, where the plywood is directly attached to the subfloor, the recommended plywood flooring thickness typically ranges from 5/8-inch (15mm) to 3/4-inch (19mm). While 3/4-inch plywood is standard for most residential subfloors, certain conditions may require thicker plywood.
Our underlay rolls cover 15.07 square metres; simply multiply your length by your width (to get the total square meters), and divide it by 15.07 and you will know how many rolls of underlay you will need.
Density plays a role in both comfort and durability. Higher-density underlay tends to be more resilient and durable, as it can better withstand the pressure and weight placed on the flooring surface. It offers improved support and helps prevent premature wear and tear of the floor covering.
So, when deciding which carpet underlay – rubber or foam – remember that rubber will last longer, and offer greater impact resistance, but PU foam will be softer, warmer, quieter, and cheaper.
We'd like to get one thing clear from the start – underlay thickness does matter. Getting it right can make a huge difference to the final look and feel of your new flooring, having a significant impact on its underfoot comfort, sound and heat insulation, and longevity.
When moisture penetrates your flooring, it can cause mold, mildew, and the potential for water damage. A moisture barrier helps control the water vapor's movement to help protect your floors. Therefore, if you're installing floors in an area that sees moisture, even a little, a vapor barrier is needed.
No subfloor is perfectly level, but any signs of unevenness and high or low spots must be remedied. Please follow these requirements: Subfloor unevenness cannot be greater than 3/16 of an inch over a 10-foot span or 1/8 inch over a 6-foot span. Subfloors must not slope more than ½ inch per 6 feet (25 mm per 1.8 m)
It comes in two different weights: 15- and 30-pound, with 30-pound being the more durable, heavy option. Synthetic roofing underlayment is typically made from durable polymers that are created to be water-resistant and easy to work with. Many roofing contractors prefer to use synthetic roofing underlayment over felt.
So, underlayment on low-slope roofs should overlap 19 inches. Remember that underlayment on steep-slope roofs should overlap 2 inches. Also, remember that asphalt shingles should never be installed on roofs having a slope of less that 2:12. The difference is easy to see, once the underlayment is installed.
In most cases, traditional felt underlayment is rated to last between 12 and 20 years. In other words, in a little over a decade, the underlayment beneath your roof's surface may start to deteriorate. The roof will become more prone to leaks as this added layer of protection breaks down.
Ball & Young supply underlay from 3mm all the way through to 11mm; the thicker the product, the more travel of compression there is, which makes the product feel more comfortable and gives better heat insulation.
There is no fastening the underlayment to the subfloor. However, during installation some installers like to fasten underlayment to the subfloor to prevent the underlayment from moving. If your choose this route, staples are a good choice to fasten the underlayment.
The short answer is that doubling up on underlay is not recommended and, in fact, can cause more harm than good.
The high cost of synthetic underlayment is due to its superior material strength and long lifespan compared to felt or asphalt paper underlayment. While the initial investment may be higher, synthetic underlayment can save you money in the long run by lasting longer and requiring fewer repairs or replacements.
Underlayment grades of plywood have a solid, touch-sanded surface for direct application of carpet and pad. For areas to be covered with resilient floor covering, specify panels with “sanded face,” or certain other grades as noted in Table 1.
Generally, there are five thicknesses in the following thickness categories: 1/4, 11/32, 15/32, 19/32 and 23/32. The thinner panels are often used for an underlayment under resilient flooring products in conjunction with a thicker subfloor, while thicker panels are used for hardwood and tile flooring.