Posted By: AMG1.5-2m metres above seal level

oink oink!

What does 'sea level' mean here? mean between hi and lo tides, or 100yr high tide or something? If the former it already sounds v slim; if the latter then I guess shd see you thro for a century or so - but the danger will be storms and tidal surges that go way higher than hitherto deviations from mean. All will depend on the sea wall - plenty of times waves will peak higher than your garden?

The other thing will be water table, which will be saline?

I'd certainly consider selling; it depends on your resistance to stress & financial position. In particular you may be able get insurance now, but that may become impossible in the future. I imagine that would restrict the potential buyers if you sell later - which may or may not bother you.

Options if you stay? Maybe:
Build a second floor containing all the key rooms, or at least convert the loft? Even rebuild on a pontoon?
Build an elevated parking space
Install everything necessary to live off-grid, even if only as a backup
Fit an anti-backflow device to the drain(s), so you don't get sewage pushed back up into the house
Move all low electric outlets to door handle height
Position all kitchen electrical devices (cooker, washing machine, fridge) above worktop level
Build kitchen 'units' in brick, rather than installing chipboard cupboards - or use commercial stainless steel units
Replace the ground floor with solid (calculating to make sure the insulation won't float it!)
Use tiles / other water-tolerant floor coverings
Replace gypsum plaster / plasterboard with lime plaster & breathable paint
Don't use water-sensitive cavity wall insulation

Of course most of those are precautionary rather than preventative.

The environment agency do a guide to flood protecting houses so Id start by reading that.

First thing Id look at is how big is the flood plain behind the sea wall. If its small then it wont take much overtopping to get damaging water levels around the house. If its a large flood plain then likely youll not get the water very deep. Remember than so long as the defences dont fail, the tide is only at its highest for an hour or two.

Unless you excavate around the house and fully repoint down to foundation level, brickwork will likely always leak. Youll likely get water coming in through the walls, air bricks, gas/electric cables/ducts, sewers etc etc. If you seal up all those and make some 1 metre high boards to seal doors, Id use the space under the suspended floor as a sump and install a fair size submersible pump powered from a generator stored above 1 metre or in the loft with the exhaust vented outside.

Because your thinking about flooding and probablg taking some action, youll probablh never have s problem🤞

My 2d worth is wot Shevek said.

Posted By: philedgeIts difficult to say if someone should sell up without knowing the details. Theres definitely no exodus from our area😁

The problem is when it becomes easier to know—when you have the details—it will be too late. Nobody will want to buy and it may become uninsurable.

And even if one's coastal property isn't physically at risk, that may not matter if properties near by are, because people will start thinking as above.