The biggest problem that we have at the moment in building the homes that we want is the global market situation. So, as I described at the beginning, the price inflation has been pretty awful, and that's the case for social, so about 30 to 35 per cent extra for each home that we build in the social sector, and that's also happening in the private sector, so obviously that's driving some of the price inflation, as well as the heated housing market. So, trying to make sure that, in particular, our SME builders stay in business while that's happening has been one of the things that we've been looking to do. As I say, we run a construction forum, where we engage with them on a very regular basis and try and make sure that there is at least a Government pipeline of work to keep them going, so that they don't have real bad cash flow, although, I mean, that's not to say that we can solve every problem, because we haven't been able to.
And, absolutely, the whole issue about access to land and the land values—that's what Neil's reminded me of. So, what we've been doing is developing a different system for the way that we support social housing, so that we look at the affordability of the site overall, rather than a single intervention rate. So, for many years, we've had a single intervention rate, but obviously there are some areas in Wales that have a high enough land value to not need that intervention and there are other areas that need a higher intervention rate to make the houses buildable. So, we've been pulling all the levers we can to do that.
I've also had lots of meetings with the big house builders in Wales, which have been surprisingly helpful in some areas. We haven't always seen eye to eye, but actually, we've seen more eye to eye than people would, perhaps, expect. And many of the bigger house builders have actually embraced our new standards for all kinds of reasons, not least that we've been enabling, as I say, the social house buyers to buy off-plan, which really helps with a mixed community.
We have a huge issue with the phosphate and nitrate issue, on which I'm hoping that the First Minister is going to chair a summit, possibly at the Royal Welsh, with a whole series of interested parties, about how on earth we're going to get underneath that problem. That's a very, very difficult problem with no obvious solution to it—we need to attack that on a number of fronts. And then, this whole issue about making sure that the land supply is there and that we have all of the levers I talked about earlier about building on brownfield, in particular, and those funds to make sure that builders can remediate the property—you know, remediate the land before it goes on.