Durham plots slope. The Wear banks do, and so do gardens in villages such as Witton Gilbert. A single deck built out from the back door soon leaves the ground. The downhill edge needs guarding, the posts get long, and the height may no longer fit permitted development. Our team splits the deck. An upper level at the door. A lower level further down the bank. Steps between them. Air under both.
Two levels, not one tall frame
The upper deck is the one you step onto from the house. It is sized for a table or a landing, not for the whole garden. It stays within 30 cm of the ground around it whenever that is what the rules and the door allow. The lower deck sits where the slope has dropped, again close to the ground at that point, so you are standing on the bank rather than above it. The view, if there is one, is still there. The structure is calmer.
Split levels use more posts and more steps, and they keep each surface near the garden. The Wear-bank guide is how we measure the fall before choosing.
The junction between the two frames is a step or a short flight, not a ramp disguised as boards. Rises are equal. The tread is deep enough for a wet shoe. A landing at the door means you are not stepping backwards onto a stair. Guarding is fitted where a drop between levels, or at the lower edge, needs it. Where both decks are genuinely low, we do not add rails for show.
How the frames meet
Each level has its own posts and footings. We do not hang the lower deck off the upper one as an afterthought. The ground between them is still a bank, and it needs to shed water without washing soil into either void. The uphill edge of the lower deck is the vulnerable one: soil and leaves travel downhill into it. We detail a stop and a clear gap, then leave the outer edges open so air can cross. Ventilating a Durham deck is the rule for both platforms. Two levels double the void, and they double the chance of blocking it if we are careless.
Joists are spaced for the board, composite or timber, the same on both levels so the surface reads as one job. A change of board between levels looks like two unrelated schemes. Fascias finish the edges you see from the garden below, which on a bank is the view that matters. Fixings are the ones the board and the damp valley require. The lower deck often stays wetter. It does not get a lesser frame.
On a slope the posts differ in length, so we brace as the heights require. Trial holes at each post matter, because a bank changes. The BGS Geology Viewer is the map. The hole is the decision.
Steps and the way you use them
The flight is part of the service, not a ladder between two decks. We set it wide enough for the garden, in line with the door or to one side if the side is how you reach the lower lawn. Equal rises, closed risers if a gap would catch a foot, and a surface with grip when the Durham damp is on it. If the drop between levels is a single comfortable rise, it is one wide step, not a flight invented to look important.
We ask who will use the flight, and we keep a route so the voids can be cleared. A steeper going that suits only one person is the wrong flight.
The flood map is read for the lower level especially. We do not place that platform in a part of the garden the map marks as a concern without saying so. We also do not invent a zone for every sloping address. High banks and valley floors are different. The visit separates them.
Permission and the quote
Each level is checked against the ground beside it. If either would stand more than 30 cm above that ground, we say so. Half the garden includes both decks plus sheds and extensions. Nothing goes forward of the front wall. Conservation areas remove permitted development for decking at the side, which matters when a slope wraps around a house. Listed buildings have no permitted development for decking in the garden. The peninsula's World Heritage limits are an address check, described in the peninsula guide. None of these are waived because the garden is steep.
The quote lists both levels, the steps, any guarding and the ventilation. Ask for a quote with the postcode and a sentence on how the garden falls. We measure the drop and say whether two levels are needed, or whether one low deck and a step will do.
FAQ
When is one deck enough?
When the fall is small enough that the whole surface stays close to the ground. We measure. If the lower edge would be high, we split.
Do both levels need air underneath?
Yes. The lower one is often damper. Each frame has an open void, and the uphill edge is stopped so soil does not fill it.
Are split levels a way around the height rule?
No. Each platform is judged on its own height above the ground beside it. A tall lower edge is still tall.
Can the steps be wide?
Yes. The flight should be comfortable in the wet, with equal rises. A single wide step is enough when the drop between levels is small.
