The cost for your loft conversion can vary wildly and depends largely on what kind of loft you are seeking to put in place. Here are three points to consider before you make any decisions.

1. Planning Consent

Here in England we are lucky in at least one respect, in that planning permissions for loft conversions were largely done away with in late 2008. This has reduced delays associated with planning applications, as well as the uncertainty about whether they will be granted.

However, whether you live in England or another country, conditions still apply. In England, if your loft conversion is to exceed 40 cubic feet on a terraced house, or 50 cubic feet on a detached or semi-detached house, then you still have to apply for consent, and even if you are within this limit there are certain other conditions, so ensure that you are either in the clear or do take the cost of getting consent (anything up to 1,000) into account.

2. Avoid getting an expensive storage loft

The most financially beneficial return on your investment in a loft conversion comes when you can use the additional space created as a bedroom, preferably with an en suite bathroom, accessible from a staircase extension that has been built to look like part of the original staircase (even though it has to be enclosed with a fire resistant door).

If this increases the number of bedrooms from three to four then the increase in the value of your home is the greatest. But it isn't possible with all houses. If your house was built since the 1960s then it's quite possible the pitch of the roof and the way the roof is constructed will make a loft extension unfeasible.

The extra space will only be of any practical use if at least half of it can be used as a regular room, where you can walk upright in it without falling over trusses. If the joists separating the loft from the rooms below were only designed to support a ceiling then they will need reinforcing or even replacing with steel joists that are lightweight yet strong enough to bear the extra weight to be placed on them.

Other practical uses for the additional space created is for a home office or a teenage recreation room, or even, yes, as storage space as long as the cost of conversion is minimal.

3. Factor in all the costs

The average cost overall of a loft conversion in England at the present time (summer 2012) is between 20,000 and 30,000, but this can easily rise to 40,000, depending on the circumstances and geographical location.

Even if you don't need planning consent, you still have the costs of an architect to draw up the plans (around 500 to 1,500), the stairs (including fire resistant door), adequate ventilation and lighting, a structural surveyor, adequate joists, and plumbing and electrics, together with decorating.

You can save on the costs of the last two items if you are in any way capable of some DIY. The rest of the work is best left to the professionals. But the upside to all this expense is that the cost for loft conversion can very quickly be recovered in the form of an increase in the desirability and market value of your home.