Traditional Spring Sliding Sash Windows
Verified by manufacturer 1 day ago
UL Certified
Certificate type
Health & Safety Accreditation
Certificate type
Traditional single spring timber sash windows.
Application
Suitable for mid-range new developments, as well as replacing classic windows on non-listed buildings.
Description
Our Spring Sliding Sash Windows retain the appearance of a classic sash while using a modern spring balance system in place of cords and weights. This makes them slimmer, easier to install, and straightforward to operate, while still providing smooth sliding movement.
Each window is manufactured in engineered timber, available in redwood, hardwood, Accoya or oak, and finished with a durable three-coat factory-applied paint or stain. With U-values as low as 1.4 W/m²K and acoustic ratings up to 39 dB, they meet today’s performance expectations without compromising style.
Options include applied glazing bars, varied cill projections, concealed trickle ventilation, and a choice of ironmongery finishes.
Tested for weather resistance and designed to last for around 60 years with maintenance, these Spring Sash Windows provide a practical, long-term solution for both traditional and modern properties.
Features and benefits:
- They deliver classic style, but incorporate a simpler, more compact and modern spring balance mechanism in place of weights and pulleys.
- Double-glazed as standard, they are available with safety glass, obscured glass, acoustic glass or solar control glass. Triple glazing is also available to special order.
- Twin gasketing ensures reliable weather containment.
- Bespoke windows and doors are available; consult manufacturer for details.
- FSC certified.
Guarantees:
TRC Contracts Ltd offers robust guarantees on all TRC window ranges we supply and install. The following general terms apply on all new windows:
- Expected Lifespan: All our windows are designed with a 60-year service life guarantee.
- Manufacturing and Material Defects: ten-year guarantee.
- Finishes: The standard three-coat opaque finished joinery is guaranteed for ten years, and the stain finishes are guaranteed against blistering or flaking for six years.
- Seals: The seals on double-glazed units are guaranteed for ten years (from the date of delivery).
- Ironmongery: Functional failure is guaranteed on ironmongery for two years.
General information
Color | Black Brown White Manufacturer guidanceMultiple options available. RAL classic range. |
Finish | Painted Manufacturer guidanceAvailable in dual finish, RAL classic range and Stain. Insert requirements. |
Material | Timber |
Shape | Rectangle Guidance for specification option: Special shapes available |
Length | Bespoke |
Width | Bespoke |
Height | Bespoke |
Warranty description | Ten year |
Uniclass | |
CAWS | L1/304 Wood windows L10/210 Wood windows L10/10 Wood windows |
Specification data - Wood window units
Classification data | |
Standard | To BS EN 6375-1, EN ISO 10077 and ISO 9001. |
Third-party certification | FSC Certified. |
Dimensions and configurations | As drawings. Guidance for specification option: Insert requirements. As schedule. Guidance for specification option: Insert requirements. |
Product performance | |
Fire performance | |
Fire egress | Yes. |
Weather performance | |
UK exposure category | To BS 6375-1, 1600 Pa. |
Air permeability | To BS 6375-1, Class 4. |
Watertightness | To BS 6375-1, Class 4A. |
Resistance to wind load | To BS 6375-1, Class A4. |
Durability | |
Operation and strength characteristics | To BS 6375-2. |
Safety | |
Security level | To PAS 24. |
Environmental | |
Background ventilation | Concealed trickle vent. |
Acoustic performance rating | To BS EN ISO 717-1, 36 (0;-3) dB. |
Thermal | |
Whole window U-value | To BS EN ISO 10077-1, ≥1.4 W/m²K. |
Frame | |
Profile | Ovolo. Lambs tongue. Manufacturer guidanceBespoke profile options available. |
Wood species | Engineered Accoya. European oak. Engineered hardwood. Engineered redwood. |
Chain of custody | FSC. |
Appearance class | For opaque finishing: to BS EN 942, J10 for glazing beads, drip mouldings and the like. J40 or better for all other members. |
Finish as delivered | Factory finished. |
Preservative treatment to wood components | Preservative treated. |
Ventilator | Trickle ventilator, EA 1700, 4400, 5000 mm². |
Frame horns | Not required. Type H1. Type H2. Type H3. Type H4. Type H5. Type H6. |
Glazing or infill | |
Standard | Relevant parts of BS EN 1279. |
Requirements | 24 mm double glass unit. Guidance for specification option: 4 mm tough/ 16 mm argon/ 4 mm tough low-E - As standard. 24.8 mm sound control double glazed unit. Guidance for specification option: 6.8 mm sound control laminated/ 14 mm argon/ 4 mm tough low-E. Special order. |
Hardware | Sashes are hung on spiral balances. |
Operation | |
Type | Manual. |
Electrical supply | None. |
Fixing features | Guidance for specification option: Project specific. |
Frame | 55 x 160 mm (lining width x frame depth), manufactured using mortise and tenon joints, glued and mechanically fixed. |
Sash | 39 x 55 mm top rail and stiles, 90 x 55 mm bottom rail, 45 x 55 mm meeting rail. |
Mullion | 110 mm wide (70 mm for triple sash with fixed outer sash). |
Sill section (height x depth) | 54 x 160 mm. |
MoistureContent | 12–19%. |
Glazing beads | Internally beaded. |
Sill | Solid hardwood. |
Weather seal (factory applied) | The window is fully weather sealed to BS EN 6375-1. |
Sill projection | 35 mm. 50 mm. 60 mm. 70 mm. 80 mm. 90 mm. 100 mm. 110 mm. |
Windowboard groove | Required. Not required. |
Internal Glazing Bars and/or Perimeter Bead | 18 mm lambs tongue type 2. 18 mm ovolo profile type 2. 22 mm lambs tongue type 1. 22 mm ovolo profile type 1. |
External Glazing Bars | 18 mm chamfered putty bar. 22 mm chamfered putty bar. |
Glass units | 24 mm double glass unit. Guidance for specification option: 4 mm tough/ 16 mm argon/ 4 mm tough Low-E. 24.8 mm sound control double glazed unit. Guidance for specification option: 6.8 mm sound control laminated/ 14 mm argon/ 4 mm tough low-E. Special order. Guidance for specification option: Insert requirement, safety, obscured, acoustic or solar control glass options available. |
Perimeter/Integral spacer bar | Black warm edge perimeter spacer and integral glazing bars within unit cavity. Matt chrome warm edge perimeter spacer and integral glazing bars within unit cavity. White warm edge perimeter spacer and integral glazing bars within unit cavity. |
Ironmongery | Antique brass sash fitch fastener, sash lifts, sash pulleys. Brass sash fitch fastener, sash lifts, sash pulleys. Oil rubbed bronze sash fitch fastener, sash lifts, sash pulleys. Polished chrome sash fitch fastener, sash lifts, sash pulleys. Satin chrome sash fitch fastener, sash lifts, sash pulleys. Satin nickel sash fitch fastener, sash lifts, sash pulleys. Special order. Guidance for specification option: Selected Croft ironmongery with bespoke finish is available; consult manufacturer and insert requirement. |
Trickle ventilation | Not required. Concealed through frame head trickle ventilator. |
Child restrictor | Not required. Angel lock. Guidance for specification option: Standard. Traditional sash stop. |
Sustainability data
Contains Red List materials | Yes |
Country of material origin | Lithuania |
Country of product manufacture | Lithuania |
Material | Timber |
| Carbon dioxide equivalent | |
Carbon dioxide equivalent, as defined in BS EN 15804 Self-declared | |
Stage Normalised unit (kg CO₂ eq/kg) Declared unit (kg CO₂ eq/kg) Stage:A1–A3 ('Production stage') Normalised unit : 0.5 (kg CO₂ eq/kg) Declared unit : 0.5 Lower emissions | |
Recyclability | Yes Manufacturer guidanceRecyclable parts of product timber, glass, gaskets. |
Recycled contentAs defined in clause 7.8 of BS EN ISO 14021 | 0 % |
BIM objects
NBS BIM Object Standard
This BIM object has been authored to meet the requirements of the NBS BIM Object Standard.
Find out more about the NBS BIM Object Standard.
| Platform | Compatible | Version |
|---|---|---|
 IFC | - | 1 |
 Revit | Revit 2017 | 1 |
Product certifications
Literature
Traditional Spring Sash windows
Case studies
Lorraine Road
Vauxhall Primary School
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