Choosing the Right Exterior Door Threshold: A Comprehensive Guide

19 January 2024

Selecting the perfect door threshold may seem like a minor detail in the grand scheme of building design, but its impact on both functionality and aesthetics cannot be understated. Whether you're planning for a residential entrance or a bustling commercial space, the right door threshold can make a significant difference in terms of energy efficiency, accessibility, durability, and overall performance. In this comprehensive guide, we'll explore the key considerations for door thresholds, covering both residential and commercial applications.

What are Exterior Door Thresholds and why are they needed?

A door's exterior threshold is the portion of your doorway that creates a sealed connection between your floor and the lower part of the door. Selecting the appropriate door threshold is crucial for weatherproofing your home, as it represents one of the initial measures to prevent drafts and water from infiltrating your living space.

Owing to its position, the exterior door threshold is prone to considerable wear and tear due to frequent use, household foot traffic, and exposure to varying weather conditions. Inferior thresholds may be unable to endure the demands of heavy usage, resulting in damage that could have been avoided with a more robust threshold. That’s why at SD Hardware we only stock top quality Thresholds manufactured by Exitex.

Exitex offers various types of exterior door thresholds, presenting a range of styles, finishes, and functions. There are, of course, some key considerations when selecting the appropriate Threshold.

Points to Consider when choosing an Exterior Door Thresholds

1. Energy Efficiency:

The geographical location and local climate play a pivotal role in choosing the right door threshold. In areas with extreme temperatures, heavy rainfall, or snowfall, opt for thresholds designed to withstand the elements and provide effective insulation. Our thresholds also include details on whether they are suitable for moderate or severe exposure.

Thermally broken thresholds are particularly advantageous in regions with temperature extremes, contributing to a more energy-efficient building. Typically, thresholds have a limited effect on U-values, with the greatest variance observed around 0.05w/m2k between the most and least efficient thresholds for a door. While this discrepancy may not be substantial, it becomes noteworthy if your property prioritises U-values and thermal performance. Notably, our thermally broken thresholds stand out as the most efficient options in this regard.

2. Type of Door:

Different types of doors have unique threshold requirements. Consider the specific needs of exterior doors, sliding doors, French doors, or other door types. Exterior doors may benefit from thresholds with enhanced weather resistance, while sliding doors require thresholds that complement their specific design and operation. Also, consider the thickness of the door itself and ensure that the threshold is suitable for the specific door dimensions and maintains compatibility with the door's operation. The most common door thickness is between 44mm and 58mm, so we offer a range of profiles to accommodate this and offer Thresholds that are suitable for thicker doors such as the Exitex OUM Thicker Door Threshold. Another key factor is whether the door is inward opening or outward opening. Most external doors will open inwards. This is particularly so in the case of domestic front doors.

3. Threshold Seals:

Most of our door thresholds feature one or more solid or cellular EPDM rubber seals. EPDM stands for Ethylene Propylene Diene Monomer, which is a type of synthetic rubber commonly used in various applications due to its excellent weather resistance, heat resistance, and electrical insulation properties. Also known as a gasket, these seals work through a means of compression when the door is closed. This creates an airgap which provides insulation between the interior and exterior of the property.

Some thresholds offer seals underfoot while others are designed to have seals hanging from the door itself. Hanging seals are not damaged by foot traffic and thus can potentially offer improved longevity than seals that are attached to the threshold itself. Our Exitex Kleertread and MWK thresholds have seals that are hung on the door along with an integrated rain deflector, which provides a complete weatherproofing solution.

If the seals are underfoot, they can wear over time and are likely the first part to be damaged. Fortunately, these seals can be easily replaced at a low cost. We offer Exitex T1 and T2 seals which are suitable for our Exitex OUM and MXS thresholds.

4. Accessibility Requirements:

If you or someone in your home or business utilises a wheelchair or frequently relies on crutches, we strongly suggest considering a Threshold suitable for Wheelchair Access or opting for a low threshold. This consideration is also relevant if you have young children and regularly use buggies or prams. While it may appear minor, the convenience of not having to lift the pram through the door can significantly enhance daily life.

An accessible threshold is described as one that is level or, if elevated, does not exceed a total height of 15 mm, featuring a minimum number of upstands and slopes, and with any upstands higher than 5 mm chamfered. In the case of single new build properties, compliance with Building Regulation Part M4(1) and M4(2) is mandatory. This entails ensuring that all access points to the residence, including the entrance, garden, and any terraces, are devoid of steps. Larger developments or flats may be subject to the local council's requirement for 10% of units to adhere to Building Regulations Part M4(3), ensuring full adaptability for wheelchair users.

Although extensions are not obliged to meet these Building Regulations, certain Local Authorities, Building Control, and/or Approved Inspectors might stipulate compliance with Part M4(1) as a condition within planning approval. This condition necessitates that entrances and exits to the house must be accessible. All our thresholds state if they are Part M compliant.

Low-profile thresholds or add on ramps may be necessary to ensure easy entry and exit for everyone. Most of our Exitex MDS and OUM thresholds are designed to integrate with front and / or rear ramps which can be easily added to provide smoother movement for wheeled access.

5. Heavy-Duty and Commercial Thresholds:

For heavy-duty and commercial settings, prioritise thresholds designed to withstand higher levels of traffic, heavier loads, and potentially harsher conditions. Consider factors such as traffic volume, load-bearing capacity, material strength, weather resistance, accessibility compliance, installation expertise, and security features.

SD Hardware supplies Heavy duty and Commercial Thresholds that are well-suited for use in both residential garages and beneath commercial roller shutter doors. Leakage of water under garage doors during intense storms or when snow is melting can result in harm to goods or equipment stored in your garage or warehouse. This can contribute to rust formation or create an environment conducive to the growth of mould and mildew. The intrusion of leaves, dust, and other debris poses a threat to sensitive equipment. Furthermore, the entry of cold or warm air under the door can lead to increased heating or cooling expenses.

Conclusion

Overall, investing in quality thresholds and providing regular maintenance can go a long way in enhancing the overall performance and longevity of your doors, contributing to a more energy-efficient and secure home. SD Hardware supplies a large range of Exitex standard and Heavy Duty Thresholds in a large range of sizes, so you will be sure to find the right one for your project. If you have any questions, please contact us.