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SureFast product selector

The SureFast tube and fastener range are designed to fasten insulation up to 650mm thick to any standard flat roofing deck substrate.

Scroll to show a typical flat roofing application and how to work out the correct length tube washer and fastener you need. Need to find it quickly? We also provide a quick reference table which shows the type and length of fastener you need to suit specific thicknesses of insulation.

How to select the correct tube and fastener

To optimise the benefits of the tube fastener system, the ideal combination is to use the longest tube washer length, and the shortest fastener length available. This eliminates heat loss through the metal fastener, and is more cost-effective as long length fasteners tend to cost more than long length tube washers.

First, work out the tube length. To select the tube length, deduct 15mm from the total roof build-up, to allow for insulation compression, and choose the tube of that length or shorter.

Next, the fastener length. Take the total roof build-up, and deduct the length of the selected tube fasteners. Then, add the deck penetration/embedment length (see table further down this page), and then add 25mm for to allow for the length of fastener in the tube. Then select the fastener of this length or longer.

Example - fixing 120mm insulation to 0.7mm steel deck

Tube Calculation
Insulation thickness 120mm
-15mm (to allow for insulation compression) 105mm
Maximum tube length 100mm
Use tube washer: SF-T-75 x 100
Fastener Calculation
Insulation thickness 120mm
-100mm (tube length) 20mm
+20mm (penetration through steel deck) 40mm
+25mm (amount of fastener in tube washer) 65mm
Minimum fastener length 80mm
Use fastener: SF-RS-SSA4-4.8 x 80

Penetration / Embedment depths for standard deck substrate types

Application Penetration / Embedment
Steel decking 15mm through underside
Plywood 18mm minimum thickness, 12mm through the underside
Timber decking 25mm minimum thickness, 12mm through the underside
Timber joists 35mm embedment
Structural Concrete 25mm embedment

SureFast selector chart

Total build up (mm) Tube length (mm) Drive bar length (mm) Steel Deck Concrete Deck
(subject to site pull test)
18mm plywood or OSB
SF-RS-SSA4-4.8 SF-RS-5.8 SF-RS-HCR-5.8 SS-RS-SSA4-6.1 SF-RS-6.1 SF-RS-SSA4-4.8 SF-RS-5.8 SF-RS-HCR-5.8
40 25 50 60 65 60 80 75 80 75 80
50 25 50 80 75 80 80 75 100 85 80
60 25 50 80 85 80 120 85 100 95 n/a
70 50 150 80 65 80 80 75 80 75 80
80 50 150 80 75 80 80 85 100 85 n/a
90 75 150 60 65 60 80 75 80 75 80
100 75 150 80 75 80 80 75 100 85 80
110 75 150 80 85 80 120 85 100 95 n/a
120  100 150 80 65 80 80 75 80 75 80
130 100 150 80 75 80 80 85 100 85 n/a
140 125 200 60 65 60 80 75 80 75 80
150 125 200 80 75 80 80 75 100 85 80
160 125 200 80 85 80 120 85 100 95 n/a
170 150 200 80 65 80 80 75 80 75 80
180 150 200 80 75 80 80 85 100 85 n/a
190 175 300 60 65 60 80 75 80 75 80
200 175 300 80 75 80 80 75 100 85 80
210 175 300 80 85 80 120 85 100 95 n/a
220 200 300 80 65 80 80 75 80 75 80
230 200 300 80 75 80 80 85 100 85 n/a
240 225 300 60 65 60 80 75 80 75 80
250 225 300 80 75 80 80 75 100 85 80
260 225 300 80 85 80 120 85 100 95 n/a
270 250 300 80 65 80 80 75 80 75 80
280 250 300 80 75 80 80 85 100 85 n/a
290 250 300 100 85 n/a 120 100 100 95 n/a
300 250 300 100 95 n/a 120 100 120 105 n/a

The above table details the most common insulation thicknesses but insulation up to 650mm thick can be accommodated.

Please enquire for assistance.