Glass shelves and table tops

At a glance

General descriptions: the test class, not the name, shows how a pane breaks. Where the glass is chosen is a risk decision with the supplier and the safety adviser: we found no rule that sets a type for a shelf or a table as such.

The kinds of glass, in furniture terms

A glass piece in furniture is asked four things: not to break under the loads it will meet, not to hurt anyone if it does, to survive knocks at its edges and heat from what is put on it, and to look right. The kinds differ on all four. The fuller comparison, with break patterns, lit-glass details and the safety-glazing documents for walls, doors and partitions, is on our glass types for lit joinery and luminaires sheet. This one takes the furniture view.

• Annealed (float) glass is cooled slowly. It cuts, drills and edges easily and breaks into large, sharp pieces. Float glass is described in BS EN 572-1.
• Toughened glass is heat-treated to a much higher strength and breaks into small pieces. Cutting, drilling and all edge work have to be done before toughening. BSI's scope for BS EN 12150-1 lists edgework among what it specifies and says that surface-finished glass (sandblasted or acid etched) after toughening is not covered.
• Heat-soaked toughened glass has been held hot to break most pieces carrying a rare flaw, a nickel sulphide inclusion, before they are delivered. BSI's description of BS EN 14179-1 says it keeps a known residual risk of spontaneous breakage and that it is impossible to select a quantity of it for a building and claim that no such break can occur: heat soaking lowers the risk, it does not remove it.
• Laminated glass bonds two or more plies with an interlayer, so a cracked pane stays in one sheet. BS EN ISO 12543-2 gives performance requirements for laminated safety glass. The plies can be annealed, heat-strengthened or toughened: ask for the build-up, because the plies decide how it breaks.

How much stronger is toughened glass? The National Glass Association's technical paper gives, for North American float glass, the values below. The design values are for a chance of breakage of 8 in 1,000, a load lasting under a minute, undamaged glass and four-sided support, and they apply to the glass surface, not the edge.

So fully tempered glass has about four times the design strength of annealed glass on those assumptions. That compares materials; it is not a safe load. The same paper says glass cannot be engineered like materials with a predictable strength, because what it carries depends on flaws in the surface, the type and length of the load and the chance of breakage you accept. The edge and the points where glass is held are where flaws and stress concentrate, which is what the next two sections are about.

Edges: name them, because 'polished' is not a specification

A cut glass edge is sharp. The terms used in the glass standards for the edge are, in the order of finish: as cut, usually sharp and carrying a risk of injury; arrissed (also called seamed), with small chamfers at about 45 degrees that take off the sharp margins; ground, ground to size; smooth ground, ground all over to a milky, matt face; and polished, ground and polished to a clear edge. That list is from a 2024 paper on glass edges in Glass Structures & Engineering, which sets it against the classes in the glass product standards. Pencil (a rounded edge), flat polished and bevelled are fabricators' terms that the paper does not define: draw them with dimensions instead of relying on the name.

Two points matter for a shelf or a table. First, an exposed edge on a piece people touch is never left as cut: name at least an arrissed edge, and a polished or smooth ground edge where it is seen or handled, with the corners radiused or cut. Second, a polished edge is not stronger because it is polished. The same paper reports that polished-edge strength varied widely between manufacturers, with one result below the standard's characteristic edge strength, and cautions against assuming the full standard value without proof. So do not thin the glass because the edge is polished, and ask the supplier which edge condition its calculation assumes. The paper also recommends edge protection during handling and transport for every finish and attributes defects found after processing to handling.

Supports, weight and handling

Glass seldom fails in the middle of a face. It fails at an edge flaw or where something presses on it, so the drawing of how it is held matters as much as its thickness. The three common arrangements are drawn below: pins for a shelf, a channel, and soft pads for a table top. What they share: the glass bears on a soft material, never on bare metal; there is room for it to move; holes and notches are made before toughening and kept clear of edges and corners by the supplier's rules; and the glass supplier, not the joiner or the designer, sets the span, the load and the overhang. For a table top the supplier needs the support points, the overhang, the mass of the base and the loads the table must meet. How the top is held down matters to the standards too: BSI's scope for BS EN 15372:2023 excludes a table whose top is not fixed to its understructure, meaning one that detaches when the standard's test 6 is applied, so a glass top that simply rests on pads may fall outside it. A stop stops sliding, not lifting: decide with the supplier and the test house whether the top is held down. The span and overhang arithmetic and the tipping check are on table top thickness, overhang and span.

Heat adds to the loads. A lamp close to a shelf, or a hot dish on an annealed top, warms part of the glass while the rest stays cool, which is what annealed glass tolerates worst: see the lit joinery sheet above for the principle and the questions to ask.

Weight. Glass weighs 2.5 kg per square metre for each millimetre of thickness (density 2,500 kg/m³, National Glass Association). Whole pieces, glass only:

A 12 mm top at 1,800 x 900 mm weighs about 49 kg: more than one person, a lifting method agreed with the supplier, and a delivery route checked, as in our delivery access survey. Weight also loads the base and what it stands on.

Standards, their status, and what to ask for

We found no rule that sets a glass type or a thickness for a shelf, a cabinet door or a table top as such. The safety-glazing documents we read are written for glazing in walls, partitions, windows and doors and are set out on the lit joinery sheet; for furniture the references are the table standards, the FIRA guide and the glass product standards below. Status is as seen on BSI Knowledge on 6 November 2026; none of the standards was read.

What to ask the glass supplier for, in this order:

Glass: [10] mm [clear / low-iron] thermally toughened soda lime silicate safety glass to BS EN 12150-1 [edition]; [heat soaked to BS EN 14179-1 [edition] with the process record: yes / no]. All edges [polished / smooth ground], corners [radiused [ ] mm]. Holes and cut-outs as drawing [ref], all made before toughening. Supplier's certificate of conformity for each batch. Supports as drawing [ref]; span [ ] mm; load [ ] kg per metre and [ ] kg at a point; deflection limit [ ]; the supplier's calculation attached.

Glass top: [12] mm [low-iron] [toughened and heat soaked / laminated toughened, plies [ ] + [ ] mm], [ ] x [ ] mm, corners [radius [ ] mm], edge [flat polished, arrissed]. Supported on [soft pads of [ ] mm diameter at [ ] mm from the edge] with a stop against sliding and [held down by [ ] / not held down]; overhang [ ] mm; no metal in contact with the glass. The supplier is to attach the calculation for the supports and overhang. The complete table is to be supported by a test report to the current edition of [BS EN 15372 / BS EN 12521], severity level [ ], and the supplier is to state how the top is fixed to the understructure for that test.

Laminated safety glass to BS EN ISO 12543-2 [edition], [ ] mm build-up of [ ] mm [toughened / annealed] plies and [interlayer type] [ ] mm, polished edges [with edge protection], supplied with the supplier's declaration.

The supplier is to provide, before delivery, [the certificate of conformity / the heat-soak record / the BS EN 12600 class where safe breakage is required]. Each pane is to carry the supplier's permanent mark at the position shown on drawing [ref], and is to be packed with edge protection and lifted by the method agreed with the supplier.

Standards and sources

• BSI Knowledge, status as seen 6 Nov 2026: BS EN 572-1, 12150-1, 14179-1, ISO 12543-2, 12600, 6206, 16612, 15372:2023 and 12521:2023 current. Listings only.
• National Glass Association, Glass Technical Paper FM05-12 (2023): glass density, E, strength.
• FIRA-FRQG G0001:2017, Glass in Furniture: Best Practice Guide: title and scope only; not read.
• Bukieda, Meyer, Engelmann and Weller, Glass Structures & Engineering (2024): glass edges.

Questions we are asked

Does a glass shelf or table top have to be toughened?

We found no rule that says so for furniture. The safety-glazing documents we read are written for glazing in walls, doors and partitions, and the glass standards do not name shelves or tables. Many specifiers choose toughened or laminated glass for any piece within reach because of how annealed glass breaks, and our glass and mirror page says toughened glass is the right choice for table tops and shelving. Treat it as a risk decision with the glass supplier and the safety adviser.

What thickness should a glass table top or shelf be?

No standards body, trade body or regulator gave us a minimum. Retailer and supplier pages give rules of thumb that disagree, so we do not repeat them. Thickness depends on the span, the supports, the overhang, the loads and the edge condition, and is the glass supplier's calculation or a tested design, for example by the method in BS EN 16612, with the table tested as a whole to BS EN 15372:2023 or BS EN 12521:2023. Glass weighs 2.5 kg per square metre for each millimetre.

Is a polished edge stronger than an arrissed one?

Not by reason of the polish. A 2024 paper on glass edges found polished-edge strength varied widely between manufacturers, with one result below the standard's characteristic edge strength, and cautions against assuming the full standard value without proof. Ask the glass supplier which edge condition its calculation assumes, and name every edge on the drawing.

What does heat soaking do, and does a table top need it?

Heat soaking holds toughened glass hot to break most pieces that carry a rare nickel sulphide flaw before they leave the factory. BSI's description of BS EN 14179-1 says a known residual risk of spontaneous breakage remains. It is commonly considered for large, overhead or public tops; whether a given top needs it is for the glass supplier and the safety adviser.

Can toughened glass be cut, drilled or edged after toughening?

No. Cutting, drilling and edge work are done before toughening, so the shop drawing is approved first. BSI's scope for BS EN 12150-1 also says surface-finished glass (sandblasted, acid etched) after toughening is not covered. Back-painted and antiqued glass has its own limits: see our glass and mirror page.

Which standards apply to a glass table?

For the finished table, BS EN 15372:2023 (non-domestic) or BS EN 12521:2023 (domestic), both of which include tables with glass (BS EN 15372 does not apply where the top is not fixed to the understructure); FIRA-FRQG G0001:2017 is a best-practice guide for domestic furniture with glass. For the glass itself, BS EN 572-1 (float), BS EN 12150-1 (toughened), BS EN 14179-1 (heat-soaked) and BS EN ISO 12543-2 (laminated). Check the current edition of each.