Roofing felt adhesive is a bitumen-based bonding compound used to fix roofing felt to surfaces such as timber, concrete, metal, and asphalt. It is most commonly applied at overlaps and joints between felt strips, at corners and edges, and when bonding successive layers on flat roofs. It can also be used as a cold gritting adhesive to bond stone chippings to the top felt layer for UV protection.
Bitumen Felt Adhesive for Shed, Garage and Flat Roof Repairs
MacBlair stocks roofing felt adhesive for bonding felt to timber, concrete, metal, and asphalt surfaces. The range covers cold-applied bitumen-based adhesives, used on shed roofs, garage roofs, flat roofs, and general felt repair work. Cold-applied means no naked flame is needed, making these products accessible for DIY jobs as well as trade use. Available in a range of tin sizes to suit small patch repairs or full roof installations alike.
Felt adhesive is applied by brush or mop directly to the surface. Once spread, the adhesive needs a short open time to become tacky before the felt is pressed firmly into position. Correct coverage matters: too little and the felt can lift at edges or overlaps; too much and drying time increases. Most products are best applied in dry conditions above 5°C. Typical uses include:
- Whole bonding: coating the full surface before laying felt sheets
- Lap bonding: sealing overlaps and joints between felt strips
- Corner and edge sealing on shed and garage roofs
- Cold gritting: bonding stone chippings to the final felt layer for UV protection
On shed roofs, adhesive works best at overlaps and edges rather than over the entire surface. Bitumen in the felt expands and contracts with temperature changes, so fully gluing the whole sheet down can cause cracking or tearing over time. Used at joints and combined with felt nails through the field of the felt, adhesive gives a weather-resistant finish that holds up through Northern Ireland winters. For flat roofs, adhesive is also used between successive felt layers and to bond chippings to the cap sheet.
For sealants around gutters, flashings, and upstands once the felt is down, see the sealants range for compatible products. If you are working on a larger fixing or waterproofing project, the full damp and waterproofing range includes additional treatment options. MacBlair offers click-and-collect and delivery across Northern Ireland, so orders can be placed online and collected in branch or shipped to site.
Felt Adhesive FAQ's
Clout nails are the primary fixing for shed roofing felt, but adhesive adds a meaningful second line of defence. Using adhesive at overlaps, edges, and corners helps prevent wind lift and stops water tracking under the felt at joints. On exposed or windy sites in particular, combining nails and adhesive gives a noticeably longer-lasting result than nails alone.
On shed roofs, it is generally better to apply adhesive only at overlaps, corners, and edges rather than over the entire surface. Roofing felt expands in warm weather and contracts in the cold. If the entire sheet is fully bonded to the timber, the felt has no room to move, which can cause it to crack or tear. For flat roofs with multiple layers, whole bonding between layers is standard practice and is what the product is designed for in that application.
Most roofing felt adhesives should be applied in dry conditions at temperatures above 5°C. Cold weather slows the adhesive down and can weaken the initial bond, so it is worth warming the tin slightly before use if conditions are cold. Avoid applying to wet or waterlogged surfaces. A clear, dry day gives the best results and allows the adhesive to cure properly within 24 hours.
Coverage varies by product and application method, but as a rough guide, most bitumen-based felt adhesives cover approximately 1 to 2 square metres per litre when used for bonding felt layers. Lap bonding uses less than whole bonding. Always check the specific product data sheet for the recommended application rate, as applying too thick a coat can extend drying time significantly.