According to JAR-OPS 3 a not prepared and planned EMS landing site needs at night 2Dx4D, means round about, 26m x 52m. Therefore you can count that a well prepared night landing spot, observed by pilot and well arranged with fire brigade and crew, as described from westy, needs not more. A planned landing site (as on standard hospitals or factories) needs dimensions from 1,5xD + 0,25D safety on each side, means to a BO 105 round about 25m Diameter.
The courtyard is usable from dimensions
As obstacle situation is needed: a 8° degrees angle on approach and departure on the last 245m around the landing site.
But this rule is out of service in germany, otherwise nearly no EMS flights are possible, because nearly all hospital landing sites dont't according to this rules!
Therefore the old rules are still in service (up to 2009), with an angle from 16,7°.
Thats the situation. If you plan the FATO in the middle of the 72m distance and the garages are approx. 6m high, on the direct edge of the courtyard and into the approach sector,
the field is to small.
But, i don't believe there is no free other approach sector to a fire brigade courtyard. Nearly all fire brigades have a training field or a soccer place. Also i'm shure there is a sport arena in the village or any kind of 245m free of obstacles grass field.
And: it's a questions who wants to fly. The CAA can allways give a special permission. If Eurocopter, the CAA himself or a well known VIP wants to fly...
I have made certification flights with the german CAA to helipads, only allowed to twins, with a single engine helicopter, because the CAA officer was only single rated and needed some flight hours to hold his licence current (HO HO HO)
authorities (one of them a heli examiner!!).
They are all examiners! Because they do write the names of the examiners to the paper and they are in charge. Sometimes they don't need a type rating (helicopters) or a FI, they are checking out from the cabin or the middle seat, because they are CAA officers