Decking - a couple of queries

[Charisma2]

We have a very small garden and would like to add some interest by creating a new level. We would like to lay a small area of decking approx 1.8m x 3.5m but no more than 150mm in height next to our house. My questions are as follows:

1. Can I build the decking right next to the house? What precautions do I need to take regarding the DPC?

2. Do I need to lay foundations?

3. Some other threads have talked about planning permission particularly where there are small children (of which I have 2). Would this apply in my case?

[gazzawazza]

Try this link; http://www.diy.com/diy/jsp/bq/templates/conten t_lookup.jsp?content=/bq_advice/common/howtos/ timberdecking/main.jsp

and this one; http://www.wickes.co.uk/content/ebiz/wickes/re sources/images/gil/15.pdf

Neither mention decking affecting the damp course, however the dpc is placed at a minimum height of 150mm from the ground level to prevent heavy rain from bouncing off the ground and striking above the dpc level. So in theory, placing a deck right next to the wall at the same height as the dpc (or even just below it) could allow damp to rise above the dpc level.
Having said all of this, check the level of your dpc, 150mm is the minimum height, sometimes they are higher, especially on sloping sites. If the dpc is at the same height as your decking, you could always put some flashing above the dpc to prevent splashing.

[Charisma2]

Thanks for that. We've just been to Wickes as well and got one of their leaflets!

On the subject of the DPC, the patio is less than 150mm below the damp course - it varies between 120 and 150mm. The house is not quite 3 years old and the patio was laid by the developers. There is a gap between the patio and the house which varies between 5mm and 30mm - does that make it ok? Is this something that could cause a problem later on either physically or when trying to sell the house?

[gazzawazza]

Sorry Charisma, I haven't been ignoring you, I just haven't been back on the site lately.
Just to let you know, on answering your questions, I'm speaking as a time-served bricklayer who hasn't actually worked on sites for 19 years now (change of career) although I have done lots of fiddley jobs for satisfied customers (friends) in that time.
When I served my apprenticeship, the minimum height for a DPC was 150mm, and I'm certain that this is still the case. Having said that, I really do not know whether you would be able to force the developer to relay the original patio after three years have passed.
As to your query about the gap, I certainly do not think that a gap of 30mm would make any difference, in fact I'm sure it would make the problem worse, especially if the patio sloped toward the house, allowing water to possibly drain to the foundations.
If the patio absolutely HAS TO BE higher than the minimum 150mm, I would recommend having a border of chippings 150mm wide next to the house wall and the patio sloping away. The chippings (supposedly) have the effect of preventing the raindrops from bouncing up above the DPC.
It is possible that you may never ever get a problem with rising damp, although when I'm doing a job for anyone I like to err on the cautious side and omit any potential problems.