Dig it – 3 Reasons Not to Have a Tarmac Playground: Mud, Sweat and (fewer) Tears

Swing playground

May, and its national Outdoor Classroom Day on 21st. This is a global movement to make time outdoors part of every child’s day, with two days of action each year, urging teachers take children outdoors to play and learn.

I’ve made an effort to take one class outside regularly – fortunately, the class is small enough to fit around a picnic bench, so its been easy. No special planning or change to the lesson other than that. The results of this highly anecdotal and uncontrolled experiment: the students appear to get more done, are in a lighter mood, are generally more engaged. Maybe, I’m just in a better mood? There is plenty of well-run research to back this up. Much research focuses on young children, but research on secondary-aged pupils, suggests nature has an impact on learning.

Research by Clever Classrooms found “naturalness” (the role of light temperature and air quality) contribute half of the surroundings’ influence on learning. The greatest single contributory factor was light.

The end of the school year is in sight. School leadership and site managers’ thoughts turn to those big jobs that can only be done in the holidays. It’s hard to imagine any school being short of items on that to-do list, one job worth considering is digging up your playground. Here are three good reasons to go naturel where possibel (spelling?).

  1. Mud – children’s immune systems are strengthened by playing in it. https://www.theguardian.com/environment/2025/oct/29/soil-sandpit-children-dirty-biodiversity-finnish-nurseries-research-microbes-bacteria-aoe
  2. Sweat – over a summer month, a tarmac surface will heat the surrounding air 10 times more than a grass surface, according to the compelling work of Daniel Rüdisser https://www.linkedin.com/feed/update/urn:li:activity:7392210719703863296/
  3. Tears – or the possible lack of them: studies suggest that natural environments improve communication and connections between people.

I was lucky enough to meet Professor Merideth Gattis at the launch of Learning Through Landscape’s School Grounds Collective. Over the most colourful canapes I’ve ever seen, she told me about her fascinating research into the effects of nature on our behaviour and how it has been shown to improve communication.This forms part of the growing body of academic work which highlights the non-physical role of nature on our lives. A seminal part of this was the Nature Restoration Theory, developed in the 1990s by Kaplan and Kaplan, which asserts that viewing nature has can replenish our attentional resources, specifically directional attention i.e. the type of focus needed for tasks demanding concentration and effort, like schoolwork.

Money is tight. Fortunately there are numerous sources of funding for improving school grounds. https://www.tnlcommunityfund.org.uk/funding/programmes/national-lottery-awards-for-all-england?utm_source=chatgpt.com

CIBSE Symposium 2026

Lovely to have a mention in the CIBSE Journal for the paper with Dr Stavroula Koutroumpi. On the surface, it looked like a literature review examining possible modelling techniques for including Green Infrastructure in compliance simulations, but it was more of an opinion piece.  

Reflecting on the Technical Symposium, it’s the connections that really make the event. It was a wonderful opportunity to hear what’s been on the minds of others in the industry – Tom Greenhill’s engaging presentation on the reduction of overheating made by yoghurt on windows stood out – but I particularly valued the informal discussions in the spaces around the talks. I was recommended a book I’ve been glued to, received lots of encouragement and food for thought for the paper’s main idea (#GetVegInTheRegs?), made some new connections with discussions of  collaborations underway and enjoyed an overdue catch up with Susie from Inkling and colleagues from the Bartlett.

Our paper was really about connections; those between neighbouring buildings that may shade or otherwise affect their microclimate and each other; the connections between buildings and the (currently ignored by compliance simulation) natural features around them; and the connection we have with nature. The majority of responses to the last consultation process on Part L and Part O of the Building Regs opted not to include trees because they could be cut down. How can we turn that into we are including the trees so that they aren’t cut down?

+/-40% difference in heating and cooling loads was found by Gobakis et al between models which couple the microclimate (including plants, but not just plants, also changes to view of the sky, wind speeds etc) to the building energy model.

The Australian National Home Energy Rating System (NatHERS) contains a simple methodology involving a small number of criteria (e.g. canopy dimensions, distance from building, optional shading schedule) for protected trees to be included in its models. It’s just trees and only those with a preservation order, but it’s a start: an acknowledgement of the difference trees and vegetation can make to the energy performance of buildings and to us.

A Tale Of Two Seasons

It is the best of times, it is the worst of times. February. Its my birthday month and, apart from the obvious birthday cheer, I didn’t used to find much else to like about it. Even when some friends made a tropical fruit banquet and insisted we went to the beach for a picnic, we only lasted half an hour outdoors.

But latterly, I’ve invested in a better coat and looked a little closer at February. I have changed my mind. There’s plenty to like if we look for it.

In her excellent book The Wilderness Cure, Mo Wilde (born to be a foraging teacher) lives on foraged food for a year an is looking really closely at seasonal change. She advocates for shoe-horning in a fifth season: early spring, because it is so different from late spring. There are plenty of ancient traditions giving February “new year” status. Imbolc became St Brigid’s day in Ireland which warrants a bank holiday. Its half way between the winter solstice (day length change at its slowest) and the vernal equinox (day length change top speed). If nature were a sprinter, it would be in the “set” position at the start of a race. Teetering and anticipating what’s to come.

The sun rising a whole hour earlier by the end of the month is a very welcome addition to the mornings for those up early. And it only takes a few minutes of morning exposure to the sky to spark our physiology into peak performance. Andrew Huberman does a nice job of explaining our bodies’ mechanisms – how to harness them and avoid damaging them. He recommends 5 minutes of bright sky scaled to 20 minutes for dull sky and, importantly, we need this energy rush in our eyes within the first hour of waking if we want to set everything in motion for a good night of restorative sleep. He is very insistent that we mustn’t cheat: we must be outdoors unless physically impossible.

February, in the high-ish latitudes, with it’s palpably earlier dawn, increased birdsong and glimpses of blue sky makes this a pleasure. Who needs pineapples.

green and gray scissors

LOW & NO COST ENERGY SAVINGS FOR SCHOOLS

The blackberries have peaked so a new school year must be round the corner.

Bursars trying to balance their books will continue to be challenged by high energy prices, so this week I’m dusting off the results from pilot studies we ran with five London primary schools a few years ago, in case they come in handy. A three-point summary: (1) it is possible to make substantial savings on school energy bills at little or no expense; (2) involving the whole school was recommended by site staff, was linked to increased savings and has a host of educational benefits for teachers and pupils eager for experiential learning; (3) the construction industry and academia could (and should) benefit from the data produced by students from KS2 onwards.

The project was nice: keen university students, fresh from their course, were paired with an experienced engineer or architect, to study a primary school, and quantify ways to make carbon and financial savings from energy efficiency measures and renewables. They also looked a little at wider issues like comfort. Some schools signed up for assemblies, educational workshops and meetings with site staff and teachers which appeared to make a difference to their subsequent energy savings. It made a huge difference to the ease of data collection for the students.

Each school received a useful report full of ideas and engagement activities, all free. UCL students were paid (via a GLA grant) and gained valuable experience. The construction industry consultants gave their time pro-bono (thanks again to all involved) and received insights which can be hard to find e.g. the graph to the right…

It’s a while since I taught in a primary school. I imagine that teachers are even more pushed for time these days. The project aimed to make recommendations which wouldn’t add to teachers’ workload. With that in mind, the simplest recommendation assigned two keen students as monitors to reset the classroom after each lesson so that the need for blinds-down, lights-on was assessed each day.

I’d love to hear from anyone who has tried this. Happy to share more insights. Do get in touch.

Ivy climbing all house frame

HELP FROM PLANTS IN HEATWAVES

Below is my first attempt at an infographic (graphic designers of the world, I salute you and apologise for the small font, there is much to say on this subject).

Plants are not be a heatwave cooling strategy which can be up and running today but they are effective and have many highly-desirable co-benefits. Many shrubs and trees are best planted in the growing off-season we’re heading into, so here is a summary of some practical actions which can be taken in the coming months to guard against extreme heat in future years. The long game. Hopefully there’s something amongst the five for anyone fortunate enough to have agency over their home or to be designing for others.

With so many perks when plants are used to address overheating, I wondered why they aren’t used for this purpose more often. The benefits that come to mind, on top of their shading and cooling abilities are air-quality improvements, increases to sustainable drainage area, boosts to mental health, enlargements to biodiversity habitat, carbon sequestration and possible local food production (how about, a sense of collective endeavour?). So, why isn’t this currently very widespread? One barrier is that plants aren’t (yet) welcome in compliance testing for daylight, energy use or overheating. Funny not to include these tried and tested living devices for sucking CO2 out of the air in the battle against there being too much CO2 in the air. My guess is that plants have been seen as temporary, unpredictable, maybe unreliable. This is something we need to overcome quickly. Thoughts on this, very welcome.

LinkedIn Post

RETHINKING DAYLIGHT IN SOCIAL HOUSING

Finland’s successful Housing First national policy asserts that having a good quality home is the basis for the other aspects of life (health, education, relationships….) to go well. Without a decent home, it’s hard for the rest to follow. It makes sense. Radio 4’s Rethink recently covered social housing which discussed this idea, presenting a case study of a high quality social housing scheme. Its developer emphasised good daylight levels and larger-than-usual windows, as features of high quality housing design desired by residents.

We know instinctively that daylight is good for us physiologically and psychologically. There is growing scientific evidence to back this up, (how about this wonderful paper making a direct link between daylight levels in homes and feelings of happiness) . There’s also growing research regarding the positive difference to be made by other perks of ample glazing such as a good view and connection with outdoors.

A glazed area doesn’t need to grow much to increase natural light levels from adequate to good. With joined-up thinking and design work, floor plans, shading and glass-to-solid ratios can be optimised, concerns regarding overheating and heat-loss can be minimised. So, how can we encourage good daylight levels from ample, well-designed glazing to become the norm?

For starters, here are some inspiring examples of social (or affordable) housing employing larger-than-usual windows.
Unity Place
Appleby Blue Almshouse
Central Somers Town

DAYLIGHT AND THE HOME

What a treat it was to see and hear an old friend and colleague at the Architects’ Journal Daylight in Architecture Conference a few weeks back. Hearing the case for a renewed appreciation of the health benefits of daylight was music to my ears. Ruth Kelly-Waskett spoke persuasively on the history of light in homes and how electric lighting altered our age-old relationship with daylight and the outdoors.

With mounting evidence from diverse fields such as neurology, healthcare, education (the list goes on) all pointing at the necessity of a daily daylight dose, its time for a reappraisal of our relationship with natural light. This is particularly important given that the amount of time we are tending to spend indoors.

Daylight ranks third on the list of homeowners’ priorities after energy bills and space. So, it’s about time, daylight rose up the agenda of design priorities. Health concerns around overheating, with their immediate effects on the body, have been used to determine opening sizes to date. The effects of a lack of daylight are more insidious. With a little joined-up thinking, even if the Building Regs don’t require it (yet), it is possible to consider overheating, energy consumption and daylight in the round. This holistic approach is what makes “good daylight design” and is certainly to be recommended.

CPD’s

Take your pick of our seminars: from the likely changes in the new (New) London Plan and their effect on daylight in homes, to the effects of daylight on health, environmental design rules of thumb or design tips for good daylight. We’d love to join you over lunch. Email us for details.