Frequently Asked Questions

Some of the most common questions we get asked about DrylinePro™.

Q1. How can I tell if I have a dry lined wall?

Q2. Will DrylinePro™ work if I am drilling through a dab of adhesive?

Q3. How can I find out where wires or pipes are?

Q4. Why do you not recommend DrylinePro™ for attaching cantilever or swinging arm TV brackets?

Q5. I am finding it hard to drill a hole above or beside the window for fixing a curtain rail. What could be the problem?

Q6. Can I use a longer screw to attach a thicker fixture, perhaps a one inch batten?

Q7. I have a gap of more than 10mm behind the plasterboard. Will DrylinePro™ still work ?

Q8. Can you use DrylinePro™ to securely fix to tiled dry lined walls?

 

Q1. How can I tell if I have a dry lined wall?

  • If the wall does not sound "hollow", you have a conventional plastered wall (you can use conventional rawlplugs to attach to this type of wall).
  • If you find it is generally "hollow", but with a continuous vertical or horizontal change of sound, particularly on internal walls, this is probably timber studding with plasterboard nailed to it. DrylinePro™ will not work on this type of wall and your best bet is to try to fix to the timber in the wall behind the plasterboard. 
  • If the wall sounds generally "hollow", but with occasional random, less hollow sounding areas, then you probably have a dry lined wall. This is a blockwork wall, with plasterboard stuck to it with adhesive. The "hollow" parts are between the adhesive "dabs", and the less hollow parts are where the adhesive dabs have been attached. As a final check, drill a small hole in the plasterboard. You will find that the drill goes easily through the plasterboard, then there is a gap and then you come up against the blocks. If there is no gap, you may be drilling through a dab. (see Q2).

You can use a fixing that screws just into the plasterboard for the very lightest of loads, but for anything else, you need a DrylinePro™ fixing, that grips in the blockwork wall and the plasterboard.

Q2. Will DrylinePro™ work if I am drilling through a dab of adhesive?

Yes. Just continue as normal. It should work perfectly in a dab, or between a dab.

Q3. How can I find out where wires or pipes are?

The best way is to use a wire and pipe detector available from your local DIY shop. They are not expensive and you will certainly wish you had used one if you drill through a power wire or water pipe! Be aware that this device will not find plastic water pipes that are sometimes used in new buildings.

As a rough guide, all power wires should run either vertically or horizontally from a switch or socket. 

Q4. Why do you not recommend DrylinePro™ for attaching cantilever or swinging arm TV brackets?

The poor design of many brackets means that there is a very high pluck load on the top fixings of the bracket. In our tests, DrylinePro™ handled a pluck load in the region of 70 to 120kg straight pull before failing. It is very easy to exceed this with a heavy TV on a long swinging arm. The failure usually occurs because the wall itself, being made of lightweight material, is just not strong enough.

Flat-to-wall TVs are fine. In this case, you do not get the above mentioned amplification effect of a long arm working on a small fixing area.

Q5. I am finding it hard to drill a hole above or beside the window for fixing a curtain rail. What could be the problem?

The lintel above a window is often made of either steel reinforced concrete or folded sheet steel. This can make fixing curtain rails very difficult.

Q6. Can I use a longer screw to attach a thicker fixture, perhaps a one inch batten?

Yes. The screw supplied with your DrylinePro™ kit is a 5mm x 75mm screw. (3 inch x #10 ). You can use a longer 5mm (or #10) screw, perhaps a 5x100 or 4 inch #10.

We stock a range of suitable screws: 90mm, 100mm, 120mm. Please call for pricing and to discuss your application.

Q7. I have a gap of more than 10mm behind the plasterboard. Will DrylinePro™ still work ?

We have tested DrylinePro™ with various gaps. Here are the results obtained from our testrig. All tests were conducted using a 4mm thick fixture and the 75mm screw as supplied with the DrylinePro™ kit.  Plasterboard was standard 12.5mm.

With a standard 10mm gap the fixing pulled out at around 100 kg of tensile load.
 

Gap/mm Tensile Load/kg Comment
10 100 Standard Gap
20 85  
25 70  
30 60  

We also tried a fixing through the new type of plasterboard with foam insulation attached to it. The total thickness of the plasterboard and foam, with no gap, was 50mm. This means that only 20mm of DrylinePro™ plug was in the breezeblock. This still handled a tensile load of around 50kg.

Of course, if you have a large gap, it is essential that the screw you use goes to the bottom of the fixing. If the fixture is more than 5mm thick and you have a large gap, it is worth using a longer screw. For example, if you have a 15mm thick bracket, and a large gap, use a 90mm long screw, rather than the 75mm screw supplied.

We stock a range of suitable screws: 80mm, 90mm, 100mm, 120mm. Please call for pricing and to discuss your application

Q8. Can you use DrylinePro™ to securely fix to tiled dry lined walls?

To start, you'll need to drill a 10mm hole in the tile first. We used a 'Tile Max' 10mm drill bit which is widely available online.

Mark out and carefully drill through the tile (making very sure to use eye protection as bits of tile ping of vigorously!) but try not to go right into the plasterboard. Once through the tile, change to the correct drill from your DrylinePro™ kit and continue drilling as normal.

Pop in the DrylinePro™ plug and gently screw it in to the plasterboard until the flange on the plug comes up against the surface of the tile. Fix into the plug as usual.

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Holdfast Fixings Ltd is a company registered in England and Wales.

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