How to Install Draught Excluders Properly

How to Install Draught Excluders Properly: A Complete UK Guide

If you're tired of feeling a chill creeping around your doors and windows, or noticing your heating bills climbing higher each winter, draught excluders might be the simple solution you've been looking for. These humble strips of material have helped countless UK homeowners reduce energy waste, improve comfort, and keep their homes cosier throughout the year. The best part? Installing them properly doesn't require specialist skills or expensive equipment.

In this guide, I'll walk you through everything you need to know about choosing, measuring, and installing draught excluders in your home. Whether you're dealing with draughty Victorian sash windows or modern external doors, you'll find practical advice tailored specifically for UK homes.

Why Draught Excluders Matter in British Homes

Before diving into installation, it's worth understanding why draught excluders are such a worthwhile investment for UK properties. British homes, particularly older ones, are notorious for draughts. Whether it's because of Victorian construction methods, aging wooden frames, or simply the wear and tear of decades, unwanted air leakage is a common problem that costs money and comfort.

By properly installing draught excluders around doors and windows, you can reduce heat loss significantly. The Energy Saving Trust suggests that draughts account for around 15% of heat loss in a typical UK home. Installing draught excluders is one of the quickest ways to tackle this, often costing between £10 and £50 per entry point, yet potentially saving you £20-£30 per month during winter months.

Types of Draught Excluders Available

The UK market offers several types of draught excluders, each suited to different situations. Understanding your options helps you choose the most effective solution for your particular doors and windows.

Adhesive-Backed Foam Strips

These are perhaps the most popular choice for UK homeowners due to their simplicity and affordability. Brands like Frost King and various supermarket own-brands offer foam strips in widths ranging from 10mm to 25mm, priced typically between £3 and £8 per roll. They're ideal for windows and internal door frames where you don't need heavy-duty performance. The self-adhesive backing means no nails or screws required, making installation incredibly straightforward.

Brush-Pile Draught Excluders

These feature bristles that create a seal without being too rigid. They're excellent for external doors and windows because they can accommodate slight irregularities in the frame and last longer than foam. Expect to pay £8-£15 for quality brush-pile strips. Brands like Stormguard and Weather Stripping offer reliable options available at B&Q and Screwfix.

Door Bottoms and Threshold Excluders

The gap at the bottom of doors is often the biggest culprit for draughts. Hinged door bottoms (£15-£25) and flexible threshold strips (£10-£20) are specifically designed to seal this space. These are essential for external doors and work brilliantly even when carpets create uneven floors.

Compression Seals and Tubular Gaskets

These premium options use dense rubber or silicone and typically cost £12-£30 per metre. They're brilliant for high-performance applications, particularly on frequently-used doors or in older properties with larger gaps. They require small fasteners but create an exceptionally tight seal.

Measuring Your Doors and Windows Correctly

Accurate measurement is absolutely crucial for effective draught exclusion. A poorly measured strip won't seal properly, leaving gaps that defeat the purpose entirely. Take your time with this step—it's worth getting right.

For doors, measure the height of both sides plus the width across the top. Don't measure the bottom if you're planning to install a separate door bottom excluder. For windows, measure around the entire frame perimeter where the sash meets the frame. Always add an extra 5-10cm to your total measurement to ensure you have plenty of material, and it's far easier to trim excess than to find you're short.

Before purchasing, close your door or window normally and feel for draughts with your hand or a lit candle. This helps you identify exactly where gaps exist and which areas need the thickest excluder material. Pay particular attention to the bottom of doors and the meeting rail on sash windows, as these are common problem areas in British homes.

Step-by-Step Installation Guide

Preparing Your Surfaces

This step is often overlooked but it's absolutely essential, particularly with adhesive-backed strips. Dust, paint flakes, and grime prevent the adhesive from bonding properly. Using a damp cloth, wipe down the entire surface where your draught excluder will sit. Pay special attention to corners and edges where dust accumulates. Allow everything to dry completely before proceeding—moisture prevents adhesion.

If you're working on older wooden frames, you might find the paint is flaking or the surface is uneven. A light sand with fine-grit sandpaper (around 220-grit) will create a smoother surface and help the adhesive bond better. Wipe away the dust with a slightly damp cloth again.

Installing Adhesive-Backed Foam Strips

Starting with windows: Begin at one top corner and peel back a small section of the backing paper—about 5cm. Press the foam firmly onto the frame, ensuring it sits squarely in the gap between the window and frame. Slowly peel the backing paper whilst simultaneously pressing the strip down. This two-handed technique prevents air bubbles and wrinkles.

Continue around the entire frame, mitering the corners (cutting at 45-degree angles where strips meet) for a professional appearance. At the final corner, overlap the strips slightly and trim with a sharp utility knife. For doors, follow the same process, applying strips to the top and both sides. If you're also installing a door bottom excluder, stop your vertical strips about 50mm above where the bottom seal will sit.

Fitting Door Bottom Excluders

Door bottoms are typically fitted on the inside face of the door. Position the excluder centrally on the door edge (not on the frame) so it makes contact with the threshold when the door closes. Mark the position with a pencil. If using a screw-fixed version, drill pilot holes first to prevent splitting, particularly important in older timber doors. Space fasteners every 15-20cm.

For threshold strips, centre them in the doorway and secure according to the manufacturer's instructions. Some use adhesive, others use fasteners. Test the door movement before fully securing—it should close smoothly without binding.

Working with Brush-Pile and Compression Seals

These typically come with small nail holes or require fasteners. Start at one corner, holding the strip in position and marking fastener positions with a pencil. Pre-drill holes if working with timber, then secure fasteners (usually small stainless steel screws or nails) every 15-20cm. Ensure the seal sits flush against the frame with consistent pressure—too tight and the door or window becomes difficult to operate, too loose and it won't seal effectively.

Testing and Adjusting Your Installation

Once installed, test everything thoroughly. Close the window or door normally and check for resistance. There should be noticeable pressure when closing, but not so much that the mechanism becomes difficult to operate. If a window or door sticks, you've likely installed the excluder too thick or in the wrong position—adjust accordingly.

On a windy day, hold a lit candle or incense stick around the perimeter. Any flame flicker indicates residual draughts. If you find gaps, you might need to add additional excluder material or adjust what's already there. Sometimes a second pass of foam strip in a slightly different position does the trick.

Maintenance and Longevity

Draught excluders don't last forever, though the lifespan varies considerably. Adhesive-backed foam typically lasts 2-3 years before losing effectiveness, whilst brush-pile and compression seals can last 5-10 years depending on usage and weather exposure. External doors experience more wear and should be inspected annually.

Inspect regularly for compression loss, adhesive failure, or damage. Replace strips when you notice reduced sealing performance. It's worth keeping spare rolls on hand—they're inexpensive and quick to install when needed.

Frequently Asked Questions

Can I install draught excluders on sash windows?

Absolutely, and sash windows often benefit tremendously from draught excluders due to their age and design. Apply foam strips to both the top and bottom rails where they meet the frame. You can also install strips on the sides, though be careful not to restrict the sash's movement. Brush-pile excluders work particularly well on sash windows as they accommodate the slight movement better than rigid materials.

Will draught excluders damage my paintwork?

Adhesive-backed foam can remove some paint if the surface isn't well-prepared or if the paint is already loose. Before installation on painted surfaces, test on an inconspicuous area. If paint removal occurs, it usually indicates the paint was already failing and needed attention anyway. For valuable or period properties, consider mechanical fastening options instead.

Useful Resources

🔗 Useful resource: Which? home and garden reviews

🔗 Useful resource: Energy Saving Trust