Anyone who orders glazing beads almost always faces the same question: what size should I have? Glazing beads are not sold in "narrow" or "wide", but in type code — A1, C2, D3, N5. Without a table that's gambling.
Below are all types that we supply, with their net size and rebate. If you first want to know when you need to replace beads, read replacing glazing beads with insulating glass. If you are looking for the difference between a drip bead and a cover bead, look at drip beads and cover beads.
Measure first: which three sizes do you need?
Before you dive into the table, measure three things on the frame:
- The rebate depth — how deep the recess is that the glass falls into.
- The width that the bead must cover — from the edge of the glass to the edge of the frame.
- The thickness of the new glass — single glass is 4 mm, HR++ usually 24 to 36 mm.
That third bar is often forgotten. If you go from single glazing to insulating glass, the glass package becomes four to eight times as thick. The old bead almost never fits anymore.
Glazing beads: the sizes per type
These are the flat beads, for situations where the bead does not need to drain water — inside, or outside under an overhang.
| Type | Net tomato | Rebate |
|---|---|---|
| B1 | 12 x 12 mm | — |
| E1 | 9 x 19 mm | — |
| A1 | 17 x 15 mm | — |
| A2 | 17 x 15 mm | 3 x 3 mm |
| C1 | 17 x 19 mm | — |
| C2 | 17 x 19 mm | 3 x 3 mm |
| D2 | 17 x 20 mm | — |
| SV1 | 7 x 25 mm | — |
| E2 | 17 x 27 mm | — |
| D3 | 25 x 25 mm | — |
The numbers behind the letter say something about the design, not about the size: A1 and A2 are the same size, but A2 has a rebate of 3 x 3 mm and A1 does not. The same applies to C1 and C2.
A bead with a rebate falls over the glass edge. This provides a tighter connection and protects the sealant edge. Place a bead without a rebate flat against the glass.
The O series: wide beads with deep rebates
There is the O series for thicker glazing and deeper rebates. They are 33 to 37 mm high and have a rebate that grows with the type.
| Type | Net tomato | Rebate |
|---|---|---|
| O1 | 9 x 33 mm | — |
| O2 | 12 x 33 mm | — |
| O3 | 9 x 33 mm | 3 x 17 mm |
| O4 | 12 x 33 mm | 3 x 17 mm |
| O5 | 12 x 33 mm | 5 x 17 mm |
| O6 | 15 x 33 mm | 7 x 17 mm |
| O10 | 19 x 33 mm | 10 x 17 mm |
| O13 | 25 x 37 mm | 13 x 21 mm |
| SV3 | 9 x 33 mm | — |
The number in the O series approximately corresponds to the rebate width: O5 has a rebate of 5 mm, O10 of 10 mm, O13 of 13 mm. This makes choosing easy: measure how much of the glass edge the bead should overlap and take the corresponding number.
Drip beads: the N series from N0 to N12
A drip bead has a sloping top, so that rainwater runs off the frame instead of remaining in the rebate. You use this on the outside of wooden frames.
The N series is the easiest of all, because it runs in a fixed sequence: each step is 5 mm wider, the height remains 18 mm and the rebate depth remains 5 mm.
| Type | Net tomato | Rebate |
|---|---|---|
| N0 | 18 x 34 mm | 5 x 20 mm |
| N1 | 18 x 39 mm | 5 x 25 mm |
| N2 | 18 x 44 mm | 5 x 30 mm |
| N3 | 18 x 49 mm | 5 x 35 mm |
| N4 | 18 x 54 mm | 5 x 40 mm |
| N5 | 18 x 59 mm | 5 x 45 mm |
| N6 | 18 x 64 mm | 5 x 50 mm |
| N7 | 18 x 69 mm | 5 x 55 mm |
| N8 | 18 x 74 mm | 5 x 60 mm |
| N9 | 18 x 79 mm | 5 x 65 mm |
| N10 | 18 x 84 mm | 5 x 70 mm |
| N12 | 18 x 94 mm | 5 x 80 mm |
This is how you quickly choose the right number: measure the width that the bead must cover, subtract 14 mm and divide by 5. If you arrive at 45 mm coverage, you are at N5. If you are in doubt between two sizes, take the largest — a bead that falls slightly over the rebate is no problem, but a bead that is too narrow is.
What else you should pay attention to
Solid wood or finger jointed. Our beads are made of Dark Red Meranti in one piece. Finger-jointed beads consist of short pieces of wood with a serrated bond; These are cheaper, but often cause color differences, poorer paint adhesion and weight differences.
Lengths. Glazing beads come in varying lengths, usually between 2.45 and 5.5 meters. So you don't order by the centimeter but cut to size yourself. Please allow ample time when ordering: a bead that is 4 cm too short is unusable.
Finish. Most types are primed with 80 microns in RAL 1013 (pearl white), RAL 9001 (cream white) or RAL 9010 (pure white). That base layer is not a final layer — after installation you paint in the frame color.
Sapwood-free. Sapwood absorbs moisture and is sensitive to wood rot. Beads that have been selected for this last considerably longer, precisely in the place where the frame has to process the most water.
Don't forget the blocks
A glazing bead holds the glass in place, but does not support it. The weight rests on glazing blocks in the rebate. Without these blocks, the window will rest on the frame, become stuck and may crack. You can read which blocks you need in choosing glazing blocks.
In short
- Measure rebate depth, width to be covered and glass thickness — in that order.
- Flat beads: A, B, C, D and E series, 9 to 25 mm wide.
- Deep rebate or thick glass: the O series, where the number runs with the rebate width.
- Exterior with water drainage: the N series, each step 5 mm wider.
- Order by appropriate length and saw yourself; when in doubt, choose the wider bar.
Are you having trouble measuring? Send us a photo of the rebate with the dimensions and we will find the type for you.