
Buying guides, installation notes and answers to the questions bodybuilders, fleet managers and owners ask us every week.

Shutting a vehicle up for winter is how you get wet bedding and a dripping roof. How the snow filter, a closable valve and a fan on low speed keep the air moving through the cold months.

A coach roof hatch is ventilation, daylight and an emergency exit all in one opening. Here is how to choose between manual and electric, and how the control unit ties it together.

A practical maintenance routine for rooftop ventilators, grilles and valves, with a fault-finding order for fuses, switches and controllers, and a straight answer on when a motor is worth replacing.

Heat, moisture and ammonia build up fast in a closed livestock body. Here is how to make it breathe: fresh air in low, stale air out through the roof, and extraction that works with the engine off.

The grille or valve under your roof fan sets airflow, draught control and the look of the ceiling. A fitter's guide to fixed grilles, closable valves, the V12 and the Flower Power LED valve.

Cutting a hole in a good roof feels drastic, but with a sharp hole saw, the right sealant and a tidy three-way switch, a rooftop ventilator is a half-day job. Here is how we do it.

Choosing a rooftop ventilator comes down to four questions: how much air, which voltage, what size hole, and which direction. Here is how an experienced converter works through them.

A horse trailer is a small, sealed box carrying a large, warm animal. Here is how heat, ammonia and condensation build up inside it, and how a roof extractor paired with a floor inlet puts that right.

A roof fan can only extract what it can replace. Here is why a floor ventilator turns an extractor into a working system, and how to choose and place the 129 mm and 80 mm units.

A dog in a crate in a parked van is at the mercy of the air around it. Here is how heat and humidity build up, and how a wind-driven or powered roof ventilator with a floor inlet keeps working dogs safe.

Condensation is not a leak and it is not bad luck. It is warm, moist air meeting a cold panel. Here is where the water comes from and how a proper airflow path gets rid of it.

A coach is a long room with fifty people in it. Two roof hatches, one forward and one aft, plus a powered fan for standing traffic, is the practical recipe for passenger comfort.

A camper bedroom is a small, well-insulated box full of warm, damp air. Here is how to keep it cool in summer and dry in winter without noise or draughts.

A boat is a cold shell full of warm, wet air. The cure is a small, continuous exchange of air that carries the moisture out, whether you are aboard or not.

In an ambulance the ventilation system is clinical equipment, not a comfort extra. This guide covers air changes per hour, the airflow path, why the motor's EMC behaviour matters, and controls a crew can use with gloves on.

Fitting a ventilator or roof hatch to the wrong voltage is the most common ordering mistake we see. A few minutes with the handbook or a multimeter saves a lot of trouble.