This page sets out the technical specification of Square Stainless Steel External Wall Wind Cap, Rainproof & Insect-proof Outdoor Vent Hood with Louver for Fresh Air HVAC Exhaust System as supplied by GUANDE, together with the selection rules that determine which variant suits a given project. It is written for specifiers, estimators and contractors who need to confirm a size, a material build-up and a connection method without waiting on a quotation.
| Item | Specification |
|---|---|
| Available Sizes / Models | 100mm/150mm |
| Description | Square exterior wall mounted design; surface color: dark grey; built-in stainless steel insect screen; hemispherical arc + louver rainproof structure; multiple duct diameters optional; complete mounting accessories included; billed per unit; supports customized dimensions |
| Material / Construction | High-grade stainless steel |
A square stainless steel external wall wind cap with a louvre face and a hemispherical arc rainproof structure. The shape combines a curved top that sheds water with louvre blades that break up the airflow and stop driving rain entering the duct. A built-in stainless steel insect screen keeps pests out.
Terminals are frequently the loudest component in a ventilation system, and the reason is usually self-inflicted. Air forced through an undersized opening generates velocity noise that no amount of upstream attenuation will remove. The practical rule is that terminal velocity should be kept low enough that the terminal itself makes no contribution to the room noise level, and that the duct feeding it should be one nominal size larger than the terminal if the run is short. Designers who chase small face dimensions for aesthetic reasons usually pay for it in noise.
Where a supply terminal is placed matters as much as how it performs. A supply diffuser mounted directly above an extract grille short-circuits the air straight back out of the room without ever conditioning the occupied zone. A terminal placed in a corner will produce a completely different air pattern from the same unit placed centrally. Good practice is to position supply terminals to wash the occupied zone and to keep extract points on the opposite side of the room, ideally above humidity or odour sources.
Terminals are the visible face of the ventilation system, and they are judged on appearance as much as on performance. ABS and similar engineering polymers are the default choice because they hold their shape, resist discolouration and can be finished in a wide range of colours to match ceilings. Powder-coated steel is used where mechanical protection matters. For projects with specific interior requirements, colour matching and OEM branding are routinely available subject to minimum order quantities.
Quality inspection at GUANDE is not a final gate — it runs through the whole process. Incoming raw material is checked against specification before it enters production. In-process checks monitor dimensions and surface finish at defined intervals during the run. Finished Square Stainless Steel External Wall Wind Cap, Rainproof & Insect-proof Outdoor Vent Hood with Louver for Fresh Air HVAC Exhaust System are inspected against the approved sample, and a batch record is kept against every shipment so that any issue can be traced back to its production parameters.
Our plant runs scheduled production for Square Stainless Steel External Wall Wind Cap, Rainproof & Insect-proof Outdoor Vent Hood with Louver for Fresh Air HVAC Exhaust System with typical lead times of 15 to 25 days for standard items and 25 to 40 days for custom tooling projects. We load mixed containers directly at the factory, which lets us combine several product lines from your ventilation schedule into one shipment and reduce freight cost per unit. Confirmed lead times are stated on the order acknowledgement, not estimated at enquiry.
Use the following rules when converting a project drawing into an order. They reflect how the product performs in living rooms, bedrooms, kitchens, bathrooms and corridors, where the practical limits are usually set by effective open area, throw pattern and noise level rather than by the headline dimension.
Size the run from the design air flow and the acceptable pressure drop, not from the fan spigot. Undersizing a air terminals run is the most common specification error and it cannot be corrected later without re-opening the ceiling.
Where the run passes through an unconditioned space, condensation risk — not mechanical strength — normally decides the specification. In those locations the insulated variant is the correct default and a bare equivalent is a false economy.
Keep one connector family for the whole run. Every change of system introduces an adapter, and every adapter is an additional leak path and pressure loss point.
Pairs with HDPE corrugated pipe and flexible duct. For the round equivalent see our stainless steel external wall vent cap.
GUANDE manufactures Square Stainless Steel External Wall Wind Cap, Rainproof & Insect-proof Outdoor Vent Hood with Louver for Fresh Air HVAC Exhaust System at our factory in Dezhou, Shandong, China, and ships direct to HVAC contractors, distributors and project specifiers worldwide. Wholesale, OEM and ODM programmes are welcome. Items are supplied in export cartons with the size and quantity marked on the outer label. For OEM programmes we can apply your own artwork and labelling subject to a minimum order quantity.
The products below are routinely specified alongside the item discussed in this guide. GUANDE manufactures the full range in our own plant for consolidated shipping:
Q: How does it stop rain entering the duct?
A: The curved top sheds water away from the opening and the louvre blades block wind-driven rain.
Q: Is an insect screen fitted?
A: Yes, a stainless steel insect screen is built in.
Q: Which diameters are available?
A: 100 mm and 150 mm as standard; custom dimensions can be quoted.
The southeast corner of the private entrepreneurship park in Huadian Town, Qihui County, Dezhou City, Shandong Province