20 20 roof tiles
20 20 roof tiles

What are the commonly asked questions in roof fixings?

We have compiled a list of the most commonly asked questions when fixing roofs.

  • How should the tiles on my roof be fixed?

How should the tiles on my roof be fixed?

BS 5534, the Code of Practice for Slating and Tiling states that all single lapped interlocking tiles must be mechanically fixed, and perimeter tiles (edge tiles) should be mechanically fixed using a minimum of two fixings.

Generally, roof tile mechanical fixings are a nail or screw at the tile head and a clip at the tail.  BS 5534 allows the use of suitable adhesive as a second fix where it is not possible to use two mechanical fixings. The standard recommends that all ridge and hip tiles are mechanically fixed for structural and safety reasons and to reduce future maintenance. 

The cost to the roofer to clip tiles when installing a roof can be significantly greater than simply nailing the tiles because of the extra time, labour and cost of the clips.  Therefore, roofers are keen to reduce costs and manufacturers are equally keen to improve clip design to make them cheaper, faster and easier to install, whilst improving performance; i.e. durability, reliability and greater resistance against wind uplift.

Remember to always use the clips approved by the tile manufacturer, as they will issue fixing specifications based on the test values of their particular clips.  The consequences of not using the correct clips can mean a roof that does not comply with British Standards, is not guaranteed by the manufacturer or may not be covered by building insurance. Use of tile manufacturer tile clips also ensures that the clips used have the necessary quality and durability when exposed on a roof in the UK climate, which may not always be the case if clips from other sources are used.

Online tools such as Wienerberger’s FIXSPEC allow users to input data about their project to calculate a free fixing specification based on the British Standard for Slating and Tiling requirements. 

  • What are the benefits of using dry fix systems?

What are the benefits of using dry fix systems?

“BS 8612: Dry-fixed Ridge, Hip and Verge Systems for Slating and Tiling” is the British Standard which sets minimum requirements for pitched roof dry fix systems for the first time. Dry fix systems offer a maintenance free solution and consistent, attractive finish as an alternative to mortar bedding.

One of the biggest problems with mortar is that it can be damaged by rain and frost before it has time to set. As soon as a dry fix system is installed, it is ready to face the elements. Dry fix systems can also be installed in all weather, unlike mortar which needs dry conditions.

The mechanical fixings used for BS 8612 compliant dry fix systems are weather resistant and will also withstand the highest wind loads a roof is ever likely to encounter. Some dry verge systems can be regarded as one of the roof tile fixings, so the roof tile manufacturer should be consulted regarding the suitability of the dry verge as a secondary fixing.

  • I would prefer to use mortar bedding to ridges, hips, verge etc. Is this still allowed?

I would prefer to use mortar bedding to ridges, hips, verge etc. Is this still allowed?

Since the revision of BS 5534 British Standard for Slating and Tiling in 2014, which stipulated that mortar alone could not be used to fix tiles on a roof, dry fix products have boomed in popularity. However, mortar bedding is still acceptable providing that tiles/ridges/hips are mechanically fixed in addition to the use of mortar.

Be aware that no matter how well a contractor installs a mortar bedded verge, ridge or hip, eventually the elements and natural building settlement will damage the mortar, making it ineffective. It also has a limited lifespan and requires regular maintenance because it will deteriorate in time through natural weathering.

A dry fix ridge or hip system and even visible screws or nails may not be appropriate when using very traditional materials such as, for example, handmade clay plain tiles or clay pantiles.  Heritage products are often exactly replicating was on a roof previously, which tend to be traditional roof tile designs that were not mechanically fixed at all.

BS 5534 does acknowledge that it can be difficult to find a practical or acceptable aesthetic way to mechanically fix tiles on the roof of some listed buildings, so allows the use of hydrated and hydraulic lime when using mortars for heritage work. For projects such as these, all the parties involved (client, architect, contractor and insurer) may agree to a traditionally constructed roof where the ridge and hip tiles are mortar-bedded without mechanical fixings.

 

  • How do I safely secure my roof tiles when fixing or laying my roof?

How do I safely secure my roof tiles when fixing or laying my roof?

Wienerberger have an extensive range of clips designed to suit every tile in our range. Our latest addition to the range is Monkey Grip and is suitable for use with the Calderdale Edge and TLE. Our new innovative Monkey Grip clips are super simple, super strong and super quick to use. The unique design was engineered in house by the Wienerberger Roof Technical Department. The clips provide the natural grip strength and flexibility of the animal its named after, Monkey Grip

The facts:

The clips can hold up to 45 kg force, that is 45 bags of sugar. Unique interlocking “Monkey Grip” design mean the clips stay fixed prior to hammering. The design incorporates the nail – so combined with the grip, there is no need to hold the nail while hammering (safer and easier). The nail sits further away from the tile to aid right-handed hammering. Innovative eaves clip prevents tile kick up at the eaves.

Monkey Grip logo
Monkey Grip Tile Clips

The nail is part of the clip, similar to a cable clip with interlocking design to lock onto the tile, eliminating any possible mishaps down the underlay. Designed so that the nail sits further away from the tile to aide right-handed hammering and is a perfect fit to the tile enabling you to be quicker, safer and the job easier.

Tile clip by Monkey Grip to safely and securely clip tiles.
Monkey Grip Orange Tile Clip
Tile clip by Monkey Grip to safely and securely clip tiles.
Monkey Grip Calderdale Edge Tile Clip
Monkey Grip Eaves Clips

The subtle curved design allows clip to rotate to suit any pitch. Same interlocking design as the tile clip, it always sits parallel with the tile so it does not kick up the next tile. There is also no need to hold the clip while hammering, less accidents and better efficiency.

Detail of roof fitting
Monkey Grip TLE Eaves Clip
Detail of roof fitting
Monkey Grip TLE Eaves Clip
  • Tips and advice quick links

Find products, guidance and information on how to get the most from your roofing projects.

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