Heat load & sizing

Room-by-room heat load, worked out on site

Enter the room’s dimensions, glazing, insulation and orientation and Vento works out the cooling requirement against CIBSE design temperatures — then shows how well the unit you pick covers it.

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How it works

1
Measure the room
Type the width, length and ceiling height, or bring them in from a LiDAR scan on iPhone. The requirement updates as you type.
2
Add what changes the load
Insulation, orientation, windows and occupants. Glazing comes from the doors and windows actually drawn, so a bi-fold counts as the glass it is.
3
Match the unit
Pick a unit and its coverage sits beside the requirement, so an oversized or undersized choice shows up before it reaches the customer.

The details

The working is shown

Calculation details break the total into fabric loss, solar gain, occupants and air leakage, so the figure can be checked.

A range, not just a number

Each room gets a recommended capacity band, which leaves room for the unit the customer actually wants.

Rooms that aren’t rectangles

L-, T- and U-shaped rooms are sized from their real outline, including the extra wall a U-shape has.

What it won’t do. It sizes equipment for a quote. It isn’t an MCS heat-loss certification calculation.

Frequently asked questions

Is this an MCS heat-loss calculation?

No. It sizes air-conditioning equipment room by room against CIBSE design temperatures, for quoting. It isn’t an MCS certification calculation.

Do I need a LiDAR phone?

No. Scanning a room needs an iPhone or iPad Pro with LiDAR, but every dimension can be typed in on any device.

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