Whole life costing: Kitchen furniture

Introduction

We are spoilt for choice when specifying domestic kitchen furniture. The vast majority of kitchens are made of particleboard -chipboard- construction faced with a plastics surface. Faced particleboard offers a reasonable compromise between cost, durability and appearance. Even so not all faced particleboard options are the same.

Kitchen furniture standards

Kitchen units might look wonderful but will they withstand children swinging from the doors and hot pans accidentally placed on the work surfaces? What about steam from the kettle boiling under the wall units? Thankfully specifiers can turn a range of standards which apply to kitchen furniture. These include:

BS 6222-2 for structural performance of domestic kitchen.

There are two grades of structural performance:

• Grade G - for general domestic situations where users are expected to exercise care
• Grade H – for heavy use is expected or where the users are not expected to exercise care.

To attain the standard the largest of each type of unit or component has to be tested. Grade H tests are more demanding - for example, a Grade H cutlery door is tested for wear and fatigue using a 0.33kg per cubic decimetre load for 80,000 cycles; the equivalent test for a grade G cutlery drawer is 0.25kg/m˛ load for 40,000 cycles. Carcasses, worktops, wall units, doors, hinges and other drawer types have separate tests.

BS 6222-3 for durability and adhesion of surface finishes.

Maintaining the integrity of the surface finish is critical to ensure the underlying material (particleboard or medium density fibreboard) does not get wet and swell.

BS 6222-3 should be applied to each variation of surface finish. Tests for impact, scratching, wet and dry heat as well as resistance to a range of chemicals and liquids are described. There are different pass criteria for worktops, wood lipping and all other surfaces. Laminate top surfaces and edges should be to BS EN 438-1 grade P333 which confirms degree of resistance to scratching, staining, high temperatures, burns and impacts.

Other standards

The Furniture Industry Research Association (FIRA) carries out testing of kitchen units generally to BS 6222. FIRA Gold Award is a mark of performance which may include testing to the kitchen safety standard BS EN 1153 in addition to ergonomic and environmental testing. However, the criteria needed to attain the award are unclear.

Kitchen furniture to the British Standard Kitemark should give further assurance of performance as production processes and quality assurance are reviewed.t as important as the floor structure and floor covering.

It is worth noting that testing may be selective rather than comprehensive. Curiously, there is no BS 6222-1, but do check general claims that the kitchen range you are inspired to buy meets the standard – ask to see the test certificates for units of the specific range you are interested in.

The Building LifePlans Construction Durability Database provides generic durability information for different grades of kitchen furniture. (see www.componentlife.com). This has replaced the Housing Association Property Mutual’s component life manual, which has been extensively used as a basis for performance specifications.

Materials used to construct kitchen units

Particleboard is the most common core material for all parts of kitchen units. Medium-density fibreboard tends to be used for doors.

Particleboard should be to the specification standard for this material, BS EN 312. The 2003 version of the standard introduced a new grade of particleboard: P3, a moisture resistant non-load bearing board. P3 particleboard should reduce the risk of moisture failure compared with the alternative grade P2, which is for use in dry conditions only.

Whole life performance

Thoughtful design and detailing can enhance performance over a kitchen’s life. Here are some key examples:

• It is essential to seal all cut edges of particleboard to prevent moisture ingress and particleboard swelling. Critical areas are sink insets and junctions.

• Consider mitred or butt joints for worktops rather than using aluminium or plastics jointing strips. Seal the joint with a moisture-resistant gap-filling adhesive to BS EN 204 grade D3 or D4.

• Worktops with a drip control feature to the bottom front edge reduce risk of moisture damage.

• Some manufacturers produce fully repairable units that allow damaged sections to be replaced rather than the complete unit. However, it may be worth confirming the actual costs of repairing versus replacement.

• Specify hinges which open fully into the space available so that fully opened doors back onto a vertical surface – this reduces the risk of hinges pulling out of the unit.

• Door and drawers with buffers will reduce risk of damage due to slamming.
Remember, probably the most important factor influencing the performance of kitchen furniture is the care or lack of care exercised by the users.

Specification options

Table notes

• All base units to be on supports to give at least 6mm clearance between base of unit and floor. High-pressure laminated particleboard to a minimum thickness of 15mm. All surface finishes to meet relevant tests of BS 6222-3. Third party certification (BSI kitemark or FIRA Gold Award) is assumed unless stated otherwise.

• Costs include capital costs, installation and replacement of kitchen units at the end of their service lives with an allowance for repairs. Costs are discounted at a rate of 3.5%. Costs are based on a kitchen with a storage volume of 2.5m˛. Replacement of taps and sink are included.

Costs are indicative, as there is a wide variation dependant on units specified, style and finish. Best value should be determined from a whole life assessment using project specific criteria.

First published in Building 2005

Further information

BLP provides latent defect warranties for buildings www.blpinsurance.com

Further information contact peter.mayer@blpinsurance.com or telephone: 020 7204 2450