Before choosing a place or site to put an Aga there are a few points that are to be considered for its position
Ventilation
Your Aga will more than likely need to be placed either close to an existing chimney or against an outside wall. See Chimney Flues and Twinwall Flues.
Plinth or Floor
You must make sure that your floor is strong enough to carry the weight of the Aga:
2 Oven = 1/2 Ton
4 Oven = 2/3 to 3/4 Ton
The plinth must be at least 25mm of non combustible material.
A plinth is not essential, there is no reason why an Aga shouldn't sit on the floor. But if you want to have the Aga sat at the same height as a worksurface then take:
850mm from the worksurface height for the plinth height for a Traditional Aga
840mm from the worksurface height for the plinth height for a Deluxe Aga.
The plinth dimensions should be the same as the base of the Aga:
2 Oven = 987mm wide
4 Oven = 1487mm wide
The dimension of a Deluxe plinth is 679mm from the back wall. This can be slightly reduced to 665mm if the front of the plinth is going to be tiled.
The dimension of a Traditional plinth is 665mm from the back wall. This can be slightly reduced to 640mm if the front of the plinth is going to be tiled.
No matter which type of plinth is chosen, it must be smooth and level.
Clearances
For most cases the Aga cooker can be set down right next to any of the work units you may have without risk of warping or any other damage from the heat. But the actual work tops should have at least a slight gap between it and the Aga top plate. The gap can be filled with a silicone sealant.
If the walls, around where your Aga is going to be placed, are going to be tiled then this should be done before the Aga is installed, because the tiles need to be taken below the Aga top plate level and not finished above it.
The rear wall must be at least 25mm of non combustible material.
If the wall to the right-hand side of the Aga protrudes beyond the front of the Aga, then a 125mm extra width clearance is required on the right-hand side to allow the oven door to be opened sufficiently.
If the Aga is going to be installed into a brick recess then an additional 10mm should be added to the minimum clearance sizes on either sides. This is for the natural dimensional variations found in castings.
Above the insulating covers (in their vertical/open position) there should be at least 60mm clearance.