Catalogue
Duotherm
Designed for use as fixed lights, tilt and turn, fully reversible side or top hung open out windows, internally or externally beaded for domestic and light/medium commercial applications.
Create NBS Spec Document
Product Information and Downloads
Please use the tabbing system to switch between the product information, technical specifications and document downloads.

Specification
Scope
This specification defines materials, construction, finishes and hardware for the Duotherm elite Casement Window, which conforms generally with BS 4873 specification for aluminium alloy windows. Windows described in this specification are suitable for both replacement windows into existing buildings and installation into new building work, and are designed to allow for fixing direct to masonry or into conventional sub frames of timber or PVC-U.
Materials
Aluminium Profiles
- Profiles are extruded from 6063 T6 alloy and comply with the recommendations of BS 1474.
- Sections are pre-treated and finished:-
- anodised to BS 3987, Grade AA25 to a natural self colour and other agreed colours.
- polyester powder organic coating to BS 6496 in White 9910 high gloss finish.
- polyester powder organic coating to BS 6496 in Havana Brown 8912 satin finish.
- polyester powder organic coating to BS 6496 in Black 9005 matt finish.
- polyester powder organic coating to BS 6496 in agreed colours, matt or gloss finish
- woodgrain effect finish in mahogony and light oak colours.
PVC-U Profiles
- Profiles are multi-chambered offering marvellous insulation properties and are extruded from high grade window material.
- Sections are finished either in a solid white high gloss or woodgrain efect in mahogony and light oak colours.
- Bearing Devices and Hardware
- All opening vents are hung on concealed stainless steel variable angles friction stays and fitted with (1) cockspur or (2) espagnolette or (3) espagnolette shootbolt locking mechanisms.
- To limit the opening, restrictor stays shall be fitted. The above shall be manufactured from material meeting the requirements of BS 4873.
Weatherstripping
- Weatherstripping is Q-lon set in undercut channels
Fixings
- All fixings used in construction shall be either stainless steel or other suitable corrosion resistant materials as prescribed in BS 4873.
Glass
- Glass shall conform to the requirements of BS 6262 and Part ‘N’ of the Building Regulations for both thickness and type.
- Glazing materials such as gaskets shall comply with the requirements of BS 4873.
Construction
- Frame members are mitre cut at 45° and faces coated with a suitable frame joint sealing compound. Using internal extruded aluminium corner cleats, members are abutted and securely jointed by mechanical means.
- Transoms and mullions are end milled to shape and mechanically secured to each other or other frame members with self tapping screws driven into screw receptacles in the profiles.
- All mechanical joints shall be sealed against entry of moisture.
Glazing
- External or internal, whichever is relevant to the window type chosen, aluminium glazing beads and flexible gaskets inside and out meet the requirements of BS 6262, Code of Practice for Glazing for Buildings.
- Beads and gaskets will accommodate single thickness glass 6mm and double glazed units of thickness 20mm, 24mm, 28mm and 32mm.
NOTE: The internally glazed vent frame will accept 24mm double glazed units only.
Performance
*Windows having been tested in accordance with the requirements of BS 6375 : Part 1 have achieved the following classification for weather tightness.
- Air permeability Class C 600 pa
- Water Tightness 600 pa
- Wind Resistance 2000 pa
- Test Report 3187
Product Range
- Windows are manufactured to required design to within the following maximum limitations (subject to location and conditions).
Single opening vents
1.Side Opening
- max.width 700mm
2.Top Opening
- max.height 1200mm
Subject to the agreement of Smart Systems Ltd, it is possible, in some circumstances, to exceed these limitations depending on the design criteria for weather performance and recommendations of the friction stay manufacturer.
Please contact the Research and Development Department at Smart Systems Ltd for advice.
Multi opening vents
Dependent on the design of the window and subsequent calculation results based on the mechanical strength of the profiles, type of glazing used, location and height of building.


| File Type | Document Description | Download Document |
|---|---|---|
| Duo Elite - Aug 04 Technical Fabrication Manual |
Download (4 MB) | |
| DUO CAD DUO CAD Files |
Download (2 MB) | |
| Duotherm BS6375 Part 2 (Weather) (Titon) Test Certificate |
Download (561 KB) | |
| Duotherm Casement BS6375 Part 1 (Weather) (Schlegel) Test Certificate |
Download (3 MB) | |
| Duotherm MK 2 BS6375 Part 1 (Weather) (Schlegel) Test Certificate |
Download (2 MB) | |
| Duotherm Projecting Side Hung BS6375 Part 1 (Weather) (BRE) Test Certificate |
Download (5 MB) | |
| Duotherm Windows & Doors Brochure Product brochure |
Download (2 MB) |


| Product Type | Windows |
|---|---|
| Material | Aluminium / PVC |
| Dual Colour | |
| Thermally broken | |
| NBS available |
| Max width | 1300 |
|---|---|
| max height | 1500 |
| Max weight | 50 |
| Weather suitability | |
| Acoustic suitability | |
| Thermal suitability | |
| Min Glazing | 6 |
| Max glazing | 32 |
| security rating |
| BS6375 Pt 1 | |
|---|---|
| BS6375 pt2 |
| Espag (or two point lock) | |
|---|---|
| Cockspur (or single point lock) | |
| Shootbolt (or multi-point lock) |
| Egress | |
|---|---|
| Std |
| Odd leg | |
|---|---|
| Even leg | |
| Ovolo | |
| Square | |
| Direct Fix |
| Crimp |
|---|
| light duty | |
|---|---|
| medium duty |


![[logo] Smart Systems](gfx/logo_smarts.gif)