Going to live tweet @CommonsHCLG enquiry into the planning system on now. We have @KateNHF CEO of @natfednews, @BrianBerryFMB CEO of @fmbuilders, and @PhilipBarnes_ of @BarrattHomes.

Up first is @KateNHF. She says many of the proposals are welcome - in terms of quality, transparency and speed. There is concern about capacity of current planning system, and in particular the new Infrastructure Levy and whether that is the right solution.

On developer contributions, Kate says it should be improved - not reduced in scope or abolished. Why? A chronic shortage of housing and growing economic uncertainty means we shouldn't look toward wholescale reform.

. @PhilipBarnes_ says Barratt supports a system that delivers better outcomes for developers, local authorities and communities. He recognises the need for better design, supports the proposals for binding local authority targets, and a 30 month timescale for Local Plans.

On the Infrastructure Levy, he says 'there is more work for the Government to do'. He said the report on developer contributions - here - is a good starting point. https://assets.publishing.service.gov.uk/government/uploads/system/uploads/attachment_data/file/589637/CIL_REPORT_2016.pdf

. @BrianBerryFMB echoes similar sentiment around Local Plans. There is a concern about being too prescriptive and the subjective nature of how we assess beauty, he says.

None of the witnesses have mentioned the three tier system yet around development zones. HCLG Chair, Clive Betts quips that he assumes Barratt will be happy that communities can't object to new homes under the Government's tier proposals.

. @PhilipBarnes_ says the new proposal is more democratic - difficult to see how. He says he 'doesn't apologise for being particularly bias this week' because a recent development went through democratic processes on a number occasions. He's suggesting it is too burdensome.

People can't change their mind, @PhilipBarnes_ appears to be suggesting. Clive Betts is pushing at the door, he says a presumption in favour of a tiered system could mean that Local Plans would take longer.

Why? the need to ensure the issues around the site will need to be resolved by the Local Plan, if Barratt do not favour a longer democratic process.

. @PhilipBarnes_ says more consideration needs to be given to 'white land' - which is a piece of land that isn't flood risk, green belt or an area of natural beauty. The areas that aren't designated, he means.

A 'blanket of acceptability' could be allocated in those types of locations. We seem to be on semantics here, @PhilipBarnes_ is supporting the tier system in the Government's proposals without using the language of government.

Indeed, Clive Betts pushes again and asks: is that not a blank sheet, and how is that different from the existing planning proposals. @PhilipBarnes_ says when the allocation for a site is made, there should be a design code which specifies matters

Those include scale, design, infrastructure, position of open spaces, height. If the development is not within the parameters of the design code planners should be entitled to reject the plans.

We're not getting anywhere, so over to FMB's @BrianBerryFMB. He welcomes the principle of zonal planning, but again urges caution about being too prescriptive.

In terms of community engagement, @BrianBerryFMB says local housebuilders are better placed, because they live in communities and would want to build high-quality.

. @BrianBerryFMB says better communication between developers and local authorities is needed, and he suggests a forum for developers would speed up and resolve planning applications.

Back to @KateNHF. She says the ambition of an effective planning system that is effective and sustainable is welcome - of course. To change from the existing system to a zonal planning system, however, would require a huge amount of upfront resources.

At this time of such market uncertainty, the zonal proposal is difficult to achieve.

We're now onto numbers, specifically the prescription of housebuilding numbers for local authorities. @KateNHF says there isn't an easy answer. We need a methodology that balances a broader criteria, she says.

It needs to take into account local and sub-regional expertise, and there will need to be a backstop. It doesn't take into account the potential for levelling-up, the differentiation between urban and rural, and - she says - the numbers game must be nuance. It is 'too crude'.

On allocating housebuilding numbers to local authorities, @BrianBerryFMB agrees with @KateNHF that the methodology is not yet there.

All witnesses agree - @PhilipBarnes_ doesn't think the numbers are right. He does say, however, that those numbers aren't binding.

Why aren't we building enough houses, @YasinForBedford asks witnesses. @KateNHF says one major factor is build-out rates on large, single tenure of sites under single ownership and control. She says greater diversity on sites - developers, tenure - would help.

Back to Barratt's @PhilipBarnes_, who says there is no silver bullet to building more homes. He says the fixing the planning system is the key factor preventing housebuilders building more homes - specifically the 300,000 figure.

Currently, there are 300,000 homes given planning permission a year. Planning consultants @LichfieldsUK says you need 900,000 to 1.1 million planning consents each year to build 300,000 homes a year.

Elsewhere, Chamberlain Walker Economics says you need 1.25 planning consents each year.

Planning the number one barrier - and linked to that is the availability of land - says @BrianBerryFMB. He says we need a supply of small sites to encourage local housebuilders to build.

For micro-housebuilders, the planning requirement is quite onerous, in terms of the time it takes to complete and the cost - approximately £2,000 - £7,000.

On building more tenures, @BrianBerryFMB says his clients operate in the private sector, traditionally at the upper end. He says small housebuilders are being marginalised.

Back to @KateNHF, who says for her long-term certainty over investment is a big issue. She says longer-term partnerships on larger sites would allow housebuilders to deliver more affordable tenures - it's not just planning that is a barrier.

Now onto @PhilipBarnes_, he says more complicated building - bringing in additional tenures, builders and partners - isn't going to accelerate delivery. Fair point.

On larger sites, @PhilipBarnes_ says they could be carved up to ensure they accommodate multiple builders and tenure. Ultimately though, greater complexity in the system risks the ambition to accelerate housebuilding delivery.

Witnesses are asked for their thoughts about time limits on completing Section 106s. @PhilipBarnes_: 'it would have to be very carefully imposed'. He points to the impact of COVID - and says time limits would need to be flexible enough to accommodate changes in the market.

Use of lose it approach isn't the right approach, says @KateNHF. She says we need to the deliver right homes in right places of the right quality and affordability.

Instead, we need to think about the places we want to create - in the face of desperation to build more homes. @KateNHF says she wants to see more flexibility in grants, to de-risk sites, for example, to bring forward homes as different tenures, should the market dip.

Now @pauljholmes is asking the questions. He says there are 1.3 million homes waiting to be built and asks if @PhilipBarnes_ accepts that. @PhilipBarnes_ says yes, but we need a stock of 4 to 5 million. With an additional 1 million receiving permission each year.

What impact would reducing the time limit to build out currently awarded developments have - which currently sits at 5 years - @pauljholmes asks. @PhilipBarnes_ says that's not an issue.

. @PhilipBarnes_ does add that 86 per cent of sites which get outline planning permission aren't secured by housebuilders, they're secured by landowners or agents. He says if Barratt get a site four years after consent, for example, that would be an issue.

Now @Bren4Bassetlaw asks about support for housebuilding for older people. He asks how the planning system can promote a diversity of different housing.

Back to @KateNHF, who signals toward Local Plans. In engaging with local plans, it is so important that the voices aren't of current residents, but also future residents of all ages. Interesting.

Agreement from @PhilipBarnes_, but he adds that if a Local Plan says it needs different types of tenure, Barratt will do that. He says the issue would be transition: if they've bought the site and then get a retrospective requirement they would seek a 'transition period'.

It's better to go with the market, @PhilipBarnes_ says, adding that five years ago there wasn't an appetite for a low-rise suburban rented family home, whereas now there is.

When thinking about building homes @BrianBerryFMB speaks to changing existing stock. There is less a need for office space and converting buildings could play a role, he says. Personally, I'm not a fan of permitted development rights.

How can the planning system support the growth of small and medium housebuilders, witnesses are asked. We need to see more smaller sites earmarked and allocated for smaller housebuilders, @BrianBerryFMB says.

Good point here: @BrianBerryFMB says it might be easier for local authorities to pick larger housebuilders, but apprentices are mostly employed by local housebuilders - apprentices are the future workforce.

Bad news for small housebuilders, @BrianBerryFMB says that not acting may see their decline continue - small housebuilders accounted for 23% in 2008 to just 12% now.

Does the construction industry have the capacity to build 300,000 a year, @BrianBerryFMB asked. Yes, because half of FMB members get involved of some form of housebuilding but find they cannot access the market and return to repair & maintenance. There is a huge opportunity here.

Now onto @PhilipBarnes_ - Barratt completed12,500 last year and have ambitions for 20,000 homes a year. Skills is a 'potential barrier' to hitting 300,000, but modern methods of construction would reduce the reliance on bricklayers and joiners where the pinch points exist.

Certainty over the planning system and long-term funding would enable us to reach 300,000 each year, @KateNHF says. Until then, it doesn't appear feasible.

Next question. Would raising the threshold that exempts small sites to provide affordable housing encourage larger developers to move into the small site market, @PhilipBarnes_ is asked.

. @PhilipBarnes_ said Barratt is more concerned with larger sites larger than 50, so it wouldn't move into small site market.

Thank god. @KateNHF says biggest concern of increasing the threshold for affordable homes would reduce the supply of much needed affordable housing - which would be particularly pronounced in rural areas.

For example, between 2016 and 2019 - 70% of affordable homes in rural areas were secured from Section 106, compared to 47% in urban areas.

Witnesses are asked by @rach_hopkins whether they support the Government's proposals to replace Community Infrastructure Levy with National Infrastructure Levy.

An incoming fudge here. @KateNHF: 'we really appreciate the Government's intention' for more affordable housing but we're 'not sure how the proposed solution is going to enable this'. No support.

Building on comments, @KateNHF says the proposal doesn't take into account widely varying probability and viability, and that risks promoting the most profitable schemes as opposed to the most sustainable ones.

We 'know Section 106 isn't perfect, but it did deliver 28,000 affordable homes last year' and 'ensured there was on-site provision of infrastructure relating to that development, which means communities can understand that development - it makes it more acceptable'

Continued: if proposed levy 'goes into a pot it might not be ringfenced to that development', @KateNHF says.

On creating mixed communities, zonal planning and national levy risks going back to an era of mono-tenure estates where social housing is plonked, @KateNHF says. She goes on to say she does believe the Government wants to create mixed communities.

. @PhilipBarnes_ says if Barratt are paying a local authority to deliver infrastructure, they're nervous whether they're certain it is going to deliver it. Whereas under S106, they will deliver it themselves. Seems a unfair on authorities.

From a FMB survey 55% reported that sites were unviable because of CIL. @BrianBerryFMB more sympathetic to national levy.

Second question from @rach_hopkins, who asks if small sites should be exempted from providing affordable housing and infrastructure levy requirements. For micro housebuilders it is just not viable, @BrianBerryFMB says.

The cost to small housebuilders going through process of securing Section 106 is disproportionate, @KateNHF says.

We should exempt sites that are building affordable housing schemes from the levy, @KateNHF adds.

Next question, should the levy pay for affordable housing or should existing Section 106 approach be preserved.

. @KateNHF jumping in again, in favour of Section 106. If we do have a national levy, it must contribute to affordable housing at the same level Section 106 does.

If we can get a levy that doesn't cut across the supply of housing, in principle @PhilipBarnes_ says Barratt would like to be part of the conversation.

@BrianBerryFMB says we need simplicity.

At what stage of development should the National Infrastructure Levy be charged, witnesses are asked. The current proposal is to charge at point of sale, and Barratt would support it.

. @KateNHF adds nuance. Under Section 106, currently affordable housing could be agreed at an early stage of a development. The idea of a levy being paid at the point of sale begs the question what do you do with the money: is it ring-fenced for affordable housing?

If infrastructure levy funding goes into a central pot and isn't ring-fenced, it undermines community trust and buy-in in developments, @KateNHF adds.

Moving onto issues around the green belt and zero carbon homes. @BobBlackman asks if there should be a review of the green belt and what should it cover?

Good quality natural environment that is accessible is really important, @KateNHF says. Instead, we need a strategic review. There can be a case to release sites for affordable housing, but we can also designate new sites as green belt.

Now onto @PhilipBarnes_, who says some local authorities can meet their housing needs through brownfield sites, increasing density et al. Where you can't do that, you need to review the green belt.

What worries me is a 'hands off' approach to green belt, @PhilipBarnes_ says. You don't want to force people to buy homes in undesirable places, he adds.

Good point here: @BrianBerryFMB says we need to recognise that not all green belt is lush - some of it is scrub land.

Now onto carbon homes, and the costs they add onto housebuilding. The White Paper proposes zero carbon homes by 2050, but @BobBlackman asks if we can achieve this more quickly?

Any standards that come forward must be a level playing field for any housebuilder, @KateNHF says. 2050 is too far off and we need a route map for 2050. @KateNHF adds that the real challenge is the decarbonisation of existing housing stock.

COP26 is in a year. Housing must be at the forefront of what we can do, @KateNHF adds.

Barratt has made the commitment that all homes they build will be zero carbon by 2030, and Barratt will be a zero carbon businesses by 2040, @PhilipBarnes_ says.

. @PhilipBarnes_ adds that 96% of Barratt homes are EPC B or above - compared to 2% of existing housing stock. Focusing on existing housing stock cannot be overlooked.

. @BrianBerryFMB says SMEs are building carbon efficient homes, which is encouraging, but a range of incentives would also be helpful. The real challenge, Brian reiterates, is existing building stock - and we need a retrofit strategy.

What do we need to do to encourage local authorities to co-operate on planning issues, @BobBlackman asks.

@KateNHF says Combined Authorities are working really well. They're more strategic and have their own delivery vehicle.

It's clear that greater regional devolution is a useful vehicle here. @KateNHF says there needs to be a mechanism for local authorities to work together.

Barratt is weary about additional layers of complexity and @PhilipBarnes_ asks the question whether additional layers will speed up or slow down housebuilding delivery.

The first session is coming to an end. You can watch the second tranche of witnesses giving evidence here:

https://www.parliamentlive.tv/Event/Index/e944c2ae-957c-4027-ad2e-194e752c575e