Storage units are specified by content volume and retrieval frequency. Finishes are selected for abrasion, cleanability, and maintenance access. This guide details load calculation for joinery, tolerance for installation, and finish schedules by area and exposure. All substrates, hardware, and finishes are documented before fabrication.
Storage is correct when volume, load, and access are calculated. Finishes are correct when substrate, exposure, and maintenance method are specified. There is no variance between schedule and site.
The parameters below cover capacity calculation, drawer loading, material selection, edge treatment, and tolerance. Each parameter has a measurable value and a verification method before handover.
Storage and Finishes: Capacity Calculation and Surface Specification
Storage planning is based on inventory, user reach, and load. PMC fixes capacity in litres, drawer load in kg, and access zones in mm. Finishes are specified by substrate, exposure, and cleaning method. All joinery and finishes are inspected at substrate, assembly, and installation stages.
Planning Criteria
Selection without calculation creates overload and early failure. PMC fixes the following before procurement:
- Capacity Calculation: Storage volume fixed by content list. Frequent access items between 600 mm and 1500 mm from floor
- Load Specification: Drawers rated 30 kg for cutlery, 50 kg for cookware, 70 kg for pantry. Shelves rated 40 kg per metre
- Access Zones: Door and drawer clearance 600 mm minimum. Aisle width 900 mm for single access, 1200 mm for two-person
- Finish Selection: Abrasion, stain, and moisture resistance specified by area. Test data required from manufacturer
- Tolerance: Carcass tolerance ±1 mm. Door gap 3 mm. Installation tolerance ±2 mm to wall and floor
Ad-hoc Selection vs Specified System
- Storage sized by available space vs Storage sized by inventory volume and access frequency
- Finish selected by sample vs Finish selected by substrate, exposure, and test data
- Hardware by brand vs Hardware by load, cycle rating, and adjustment range
- Edges finished on site vs Edges factory finished with documented material and adhesive
Core Specification Elements
- Joinery Construction: Carcass 18 mm BWP plywood. Back panel 8 mm. Base units with 100 mm service void
- Drawer Systems: Full extension, soft-close, load matched to content. Side clearance 13 mm per manufacturer
- Surface Finishes: Laminate 1.0 mm for vertical, 1.5 mm for horizontal. Acrylic 1.2 mm with protective film
- Edge Treatment: 2 mm ABS or PVC edge band with PUR adhesive. Machine applied, not manual
- Hardware: Hinges 110° opening, 200,000 cycle tested. Handles fixed with through-bolt, not screws into face only
Specification by Area and Exposure
- Wet areas: BWP grade substrate. Laminate or acrylic with sealed edges. Silicone at joints. 50 mm skirting in stone or tile
- High-use drawers: Tandem box with 50 kg rating. Base 16 mm. Sides metal. Bottom recessed and screwed
- Vertical storage above 1500 mm: Shutter stay rated to load. Handle at 900 mm to 1100 mm from floor
- Open storage: Edge radius 2 mm minimum. Back panel 8 mm fixed in groove. Load limited to 20 kg per metre
- Finish maintenance: Laminate cleaned with neutral detergent. Acrylic cleaned with microfiber and anti-static spray only
Budget Variables
Storage and finish cost depends on four variables. Each is fixed before execution:
- Linear metre of joinery and drawer count
- Hardware grade and load rating
- Finish type, thickness, and area
- Site conditions and access for installation
Why Load and Tolerance Precede Fabrication
- Prevents drawer failure and hinge tear-out under load
- Controls door alignment and gap consistency at handover
- Allows replacement of hardware without carcass damage
- Ensures finishes perform to test data under stated exposure
Common Specification Errors
- Sizing drawers by width without checking content weight and depth
- Using commercial grade board in wet areas without edge sealing
- Specifying acrylic without confirming substrate flatness under 0.5 mm per metre
- Fixing tall units without wall anchoring and load distribution details
- Closing panels without service access for plumbing or electrical behind
Specified storage with tested hardware and documented finishes operates without failure. PMC issues joinery drawings, load schedules, and finish schedules for approval before fabrication.
Start With Measured Inventory
Storage meets requirement when inventory, load, and access are fixed on drawing. Finishes meet requirement when substrate, exposure, and maintenance are specified. PMC provides carcass sections, hardware schedules, and finish data sheets for approval. Execution follows the approved documents with hold points at substrate, assembly, and installation.
Request a specification review to fix capacity, load, and finishes. The review covers content list, access frequency, exposure condition, and maintenance method. No fabrication proceeds without approved drawings and data sheets.
Frequently Asked Questions
- How is drawer load rating selected?
Load rating is selected by content weight with 20 percent margin. Cutlery 30 kg. Cookware 50 kg. Pantry 70 kg. Rating stated by manufacturer and verified at installation. - What substrate is used in wet areas?
BWP grade plywood with all edges sealed. Back panel sealed or WPC. Silicone applied at wall and counter junctions. Skirting in stone or tile 50 mm high. - How is finish durability verified?
Finish is verified by manufacturer test data for abrasion, stain, and moisture. Sample tested on site for colour and texture. Batch reference recorded for future match. - What tolerance is maintained for doors?
Door gap 3 mm ±0.5 mm. Alignment flush ±1 mm. Hinge adjustment range documented. Final check at handover with feeler gauge.
