Tag Archives: drainage

Drainage Around the Home

When asked at 3 years of age, “What is Dada good at?” my daughter answered, “Digging!”

Screen Shot 2018-04-06 at 9.18.50 am

Both before and after the Whanganui floods of 2015 I have focused on drainage on the farm and especially around the house where pretty much everything had been done wrong – causing a lot of water to flow underneath leading to serious damage over the last three decades.

Screen Shot 2018-04-06 at 9.23.17 am

Managing water can be done well or can be done poorly. I took this photo at work one day.

Screen Shot 2018-03-01 at 6.34.35 am

It is important to direct water away from homes. Retrofitting drainage where it has been done poorly can be difficult and expensive. Along with a number of other approaches – including cutting channels in concrete – I put in a French drain on the high-side (South) of the house.

Screen Shot 2018-04-06 at 9.18.33 am

Ironically I finished the drain two days before the 2015 floods.

Screen Shot 2018-04-06 at 9.19.25 am

The perforated pipe runs the length of the south wall.

Screen Shot 2018-04-06 at 9.20.00 am

It’s surrounded by stone and wrapped with filter cloth.

Screen Shot 2018-04-03 at 7.54.06 pm

Water flows through the stone and into the pipe.

Screen Shot 2018-04-03 at 7.53.40 pm

Stone covers the filter cloth to keep it tidy and out of the sun.

Screen Shot 2018-04-03 at 7.54.29 pm

At the southwest corner the perforated pipe enters a sump and then flows under the entire home on a gentle slope through a solid pipe to the north side, and then away from the structure.

Screen Shot 2018-04-03 at 7.55.17 pm

Any amount of drainage that directs water away from a home is important!

Screen Shot 2018-04-03 at 7.53.09 pm

Peace, Estwing

French Drains

For most people, their home is their most valuable asset.

Most homes in New Zealand are framed with wood.

Keeping water away from wooden structures is essential to keeping them in good condition.

Screen Shot 2018-04-06 at 9.19.25 am

The home we bought nearly four years ago has issues: drainage issues. Nearly everything was done poorly or wrong, and it has been a long process sorting things out.

Screen Shot 2018-04-06 at 9.18.33 am

One major project was installing a French drain along the high side of the home to reduce the amount of water making its way underneath.

Screen Shot 2018-04-03 at 7.53.40 pm

French drains come in two flavours.

Screen Shot 2018-04-15 at 5.34.02 am

I definitely favour the open drain because I a want to minimise the chances of soil or roots clogging up the drain.

Screen Shot 2018-04-15 at 5.35.15 am

I bought in a load of stone to make sure I had plenty to work with.

Screen Shot 2018-04-06 at 9.18.50 am

My daughter helped digging and moving stone.

Screen Shot 2018-04-03 at 7.54.06 pm

I couldn’t run the water around the house so I had to go under. I used a sump as the transition to a non-perforated pipe that runs on a slight slope to the low side of the house and then over the bank and down the hillside.

Screen Shot 2018-04-03 at 7.55.17 pm

In the end it makes a tidy edge to the damp side of the home.

Screen Shot 2018-04-03 at 7.54.29 pm

Peace, Estwing

Permaculture Update: Part Two

Well, it did not take long for our new “pond” to fill.

Screen shot 2015-04-13 at 11.25.57 AM

Overnight it filled with another 20-30 mm of rainfall. Now in the last 6 days we are approaching 150 mm (6 inches) of rain. Now I am thinking less about swales and more about drains. This building is at the foot of a slope and has received a lot of water in the past.

Screen shot 2015-04-13 at 11.26.07 AM

The rubble road we are building also acts as a drain for this building made of steel and wood – neither of which like water.

Screen shot 2015-04-13 at 11.26.16 AM

The water flows away from the shed and also away from the house, which suffers from serious drainage issues at the moment.

Screen shot 2015-04-13 at 11.26.27 AM

The swale has actually decreased the amount of water flowing through this gate and down the drive toward the house. That alone is a huge benefit of the swale.

Screen shot 2015-04-13 at 11.26.39 AM

Closer to home, the drain I finished last weekend is working well. It takes the water coming down the concrete pad next to the house…

Screen shot 2015-04-13 at 11.26.48 AM

…and directs it under the house…

Screen shot 2015-04-13 at 11.26.57 AM

…through a bicycle water bottle adapter (no joke) and into novoflow flexible piping under the house and out the other side.        Screen shot 2015-04-13 at 11.27.05 AM

With water it always seems like too much or too little, and the climate scientists warn us that we’ll be getting more of both in the future. Buckle up for a bumpy ride.


Peace, Estwing

Rising Damp is a Real Problem

I hang my head in shame. For the last three months I have felt like a negligent parent, having subjected my family to unhealthy conditions.

At the end of July we shifted from a warm, dry home to a cold, damp home. The new house has a large wood burner and a mammoth woodpile that was included in the chattels. During the first weekend in August I topped up the grossly inadequate ceiling insulation with R 3.6 blanket batts and figured that – along with burning heaps of dry firewood – would get us through until summer.

Unfortunately there were two factors I did not fully appreciate: 1) the winter weather would stretch into November; 2) the profound impact of rising damp.

Screen shot 2014-11-21 at 6.56.40 PM

 With the extra insulation and a fantastic heat transfer system we have been able to heat our home to healthy temperatures – 18-22 in living spaces and 16-18 in bedrooms – but high humidity inside our home has had a greater impact than I ever would have guessed.

Having never lived in a damp home, the conditions were a shock for us. My wife and daughter had persistent coughs that came and went for many weeks. I managed to escape illness, but one morning recently I pulled open the bottom drawer of a low boy to find a pair of board shorts covered in grey mould. That was the last straw! Screen shot 2014-11-21 at 6.53.20 PM

In actual fact, I knew all along that rising damp would be a problem in this home, and I bought 200 square metres of heavy-duty polythene back in August. But controlling the ground moisture was not as simple of laying the polythene under the structure – there were other issues that also needed to be addressed.

A lack of proper drainage around the perimeter of the home meant that excessive water was flowing underneath the structure. This lead to a handful of the treated piles rotting far short of their intended lifespan.

Screen shot 2014-11-21 at 6.52.34 PM

So the larger picture included drainage work, selective re-piling and laying polythene. Of these three jobs, the logical one to start with is drainage. In first aid treatment we follow the mantra: “First stop the bleeding, then treat other injuries.” The same applies to water damage and a home: “First stop the source of water, then make repairs.” Screen shot 2014-11-21 at 6.52.48 PM

While I have been slowly remediating the drainage problems, we have embraced a number of techniques for limiting the unhealthy effects of raising damp in our home. These are simple techniques that almost anyone in Whanganui can afford to do whether they are homeowners or renters.

The first crucial step was to improve sub-floor ventilation. I did so in a rather crude manner by breaking out a few pieces of Hardie Board with the intent of repairing it later. Air moving under the home picks up moisture from the ground and carries it away. Many NZ homes have inadequate sub-floor ventilation.

Another technique that is used by many people to dry their homes is to air them manually by opening windows and doors. But like many things, there are more and less effective ways to do this. The most effective way to air your home is to open it up for 10 to 20 minutes at the warmest time of the day. This is much better than leaving windows slightly open 24/7.

Finally, in order to avoid mould and mildew growth in our home we have taken a few simple steps with our furniture. I raised the low boy mentioned above with wood blocks to encourage airflow under it. Similarly I created a simple timber ‘spacer’ to move our bed away from a cold, south-facing wall. This allows airflow while keeping our pillows from falling through the gap. Win-Win.

Screen shot 2014-11-21 at 6.53.26 PM


Peace, Estwing