Concrete Block Foundations – What You Need To KnowPosted on Friday, February 6th, 2015 by Nathan Weinstock
During a home inspection, you want to have a really good look at the foundation. After all, the foundation is what does the job of carrying the house. Most houses in the Ottawa area sit on a perimeter wall foundation made of concrete, either poured concrete or concrete block.
Concrete is one of the better construction materials having good strength in compression. In other words, concrete does a great job of holding up a house. Concrete is also fire resistant and rot resistant. So basically, concrete is good.
The thing about concrete block is that, as it ages, the mortar joints in the wall can deteriorate. The foundation can lose some of its ability to hold the blocks together and thus resist lateral forces (the soil pushing sideways). This deterioration is caused by water seeping through the mortar joints and washing the cement part out of the mortar. That cement is the binding part of the mortar that holds the concrete blocks together. Weaker mortar leads to cracking of the joints (see the picture). At some point, the foundation could require remedial work to reinforce the wall.
So, a significant factor affecting the foundation’s longevity is the amount of water that passes through the wall, contributing to the deterioration. The less deteriorating water, the longer the wall life. This means that a dry block wall can perform well. On the other hand, a cracked, leaky wall may not provide long term dependable service.
The existence of cracks does not necessarily indicate a serious problem. Cracks should be monitored for changes in size (getting larger) and water penetration (leaking). If either of these occur, then further investigation is needed and remedial work may be required. That way, you can figure out what the problem is and then decide what the best fix would be.
It is important not to cover the wall and obscure the foundation from view. Don’t finish the wall unless you are sure that it is in good condition and has no water going through it. Maintain viewing access on the interior to monitor and assess the foundation condition and performance. Eliminate any water migration through the foundation. This usually means installing foundation water proofing and changing the exterior grading. Make sure that the ground around the foundation on the outside slopes away from the house. This would provide proper drainage around the foundation.
If you have any foundation cracks, they should be repaired to allow for better monitoring and to help prevent leaking. Once repaired, they should be monitored for any reoccurrence or change in size or length. Any cracks that are found to be leaking should be repaired more reliably. Any cracks that are found to be growing should indeed be investigated. This is critical to ensure that these cracks are not structurally significant. If this is the case, remedial work (which can be significant) will be required.
Inspecting Ottawa Bathroom VentingPosted on Wednesday, August 13th, 2014 by Nathan Weinstock
All bathrooms need to be vented. Really vented. I’m not talking about cracking open a window. Nobody is going to do that during a cold Ottawa winter. When I do my home inspections, I check for good, reliable exhausts in the bathrooms.
The basic bathroom, the lone toilet or the two piece powder room with a toilet and sink, needs to be vented for odours. More importantly, the bigger bathroom, the one with a tub and shower needs to be vented too, not only for odours, but also for moisture and humidity.
In ‘olden’ days, before the 1980’s, it was thought that as long as there was a window, you did not need an exhaust fan. I’ve seen so many mouldy, soggy bathrooms that had windows. During a hot bath or shower, there is a great deal of moisture given off. So much moisture that it can’t be exhausted passively.
So, you need a fan to blow the humid air, and you need a duct to carry it out. That duct starts in the bathroom and ends on the outside. The best way for a fan to do its job is to keep the duct as straight, and smooth, and short as possible. The more bends there are, the bumpier the surface, or the longer the duct is, the harder the fan has to work to get the humility out. This certainly excludes the use of plastic, corrugated dryer ducts.
Generally, the ducts end outside either on an exterior wall, or through the roof, or out the roof overhang (called the soffit). Any of theses work as long as the exhaust cap is well sealed and firmly attached. Also, it is important that the duct itself is rigid metal and fully insulated. Again, no plastic dryer ducts.
If the ducting is done wrong, and the exhaust air leaks into the attic, the consequences can be devastating (see the picture). The bathroom humidity will discharge into the attic. Here the condensation will contribute to the growth of mould. The water from condensation will also rot the wood supports found in the attic.
The bathroom humidity may also condense in the duct and leak back into the room. You can get water dripping out of your exhaust fan and think you have a roof leak. In truth, you have a poor, cold duct that is not doing a good job getting the humidity out.
So, bottom line, you should have the bathroom exhaust fan venting through to the outside on an outside wall or in the roof soffit (not into an interior space, including the attic). The fan should use a unique exhaust duct that connects to a unique exhaust cap. And make sure the duct is rigid metal and fully insulated.
Doors Open OttawaPosted on Thursday, June 26th, 2014 by Nathan Weinstock
As a home inspector, I am fortunate because I get to see inside many, many houses here in Ottawa. These can be anything from a condo apartment or townhome, all the way to some pretty magnificent mansions. And no matter what type of building it is, I always find something interesting about it.
But there are still some buildings that even I can’t get into. Nobody can. Unless you have a reason to be there or are invited. These are buildings such as embassies, offices, utility structures, even some churches and fine residences. But that all changes once a year when the City of Ottawa runs Doors Open Ottawa. This is the annual event which invites the public to visit normally restricted locations around the city. This is when some of Ottawa’s historically, culturally, and functionally significant buildings open their doors for the public’s viewing pleasure.
In the past I have had the delight of touring some remarkable buildings. These include the Transportation Safety Board Engineering Laboratory, Traffic Operations at Public Works, the Algonquin Centre for Construction Excellence at Algonquin College, and the remarkable Hydro Ottawa, Chaudière Falls No. 2 Generating Station.
This year, Doors Open Ottawa took place during the recent weekend of June 7 and 8. The highlights for me this year were being able to visit Earnscliffe, the British High Commissioner’s Official Residence, and the Embassy of the United States on Sussex Drive. At Earnscliffe, the second floor was open for viewing for the first time. It was great seeing Sir John A. Macdonald’s former house, set on the beautiful Ottawa river.
To get access to the US Embassy tour in Ottawa you have to apply in advance. I happened to remember to do that and got in for the grand tour. It is quite a remarkable building! It is great to finally see inside one of Ottawa’s more significant buildings. And, as a bonus, I got to meet the US Ambassador to Canada, Bruce Heyman. He is a very charming man. On the way out, my wife, Amanda, and I bumped into a couple of old chums (see the picture).
Save Some Heat from Your Used Hot WaterPosted on Tuesday, May 20th, 2014 by Nathan Weinstock
There’s a lot of buzz around energy savings in a house. When I do my home inspections here in Ottawa, I pay close attention to how well the house provides reliable energy performance. The main focus is generally the heating system and the building insulation. These are first and foremost in most people’s minds. What is less well known is the hot water system.
You spend a lot of money heating water in your house, for showers, laundry, and dish washing. Water heating is easy and generally quite reliable. But it is also quite costly. Water carries a significant amount of energy so it takes a lot of energy to heat up.
Once it is hot, the water goes about its business cleaning you, your clothes, or your dishes. After the hot water has done its job, away it flows, down the drain. What a shame, losing all that heat, just like that.
That is where a drain water heat recovery (DWHR) system can help. Such a system will recover some of the thermal energy that’s just thrown away down your drain. The system is a water to water heat exchanger designed for use with drain water. A drain
water (or greywater) heat recovery system captures the energy from the hot water leaving in the drain and uses it to preheat cold water entering the water heater.
The way a drain water heat recovery system works is quite innovative and elegant. This technology is simple, long-lasting and has no moving parts. The cold water coming into your house runs through a series of copper coils that are tightly wrapped around your drain stack. (See the picture.)
When someone takes a shower, does laundry, or runs the dishwasher, the warm water runs down the drain. As it goes down the drain, it transfers its heat through the copper walls of the drain water heat recovery unit. This warms the cold water coming into the house, before it goes into the water heater. The heat is transferred, but the drain water never mixes with the fresh, and your water heater uses less energy.
By recovering some of the heat that would be lost down your drain, you will use less new energy to heat your hot water. Not only do you save money, but you also reduce your carbon footprint. Less energy consumed means less greenhouse gas produced. It’s simple and you will enjoy the savings for many years to come.
Window Replacement – Which Way Is Best?Posted on Saturday, April 5th, 2014 by Nathan Weinstock
A key part of my professional home inspections here in Ottawa involves a close check of the windows, especially those that have been replaced. You see, there are two approaches to this. These are called ‘full frame’ and ‘inserts’.
The ‘full frame’ method requires the removal of ALL the old window. This includes the complete outside frame of the window. What you are left with is what’s called the rough opening, the entire hole in the wall where the original window was installed.
The ‘window insert’ approach to window replacement involves the removal of only the inner part of the old window, leaving the framing of the previous windows. The new windows are then inserted into the framing of the previous windows.
The preferred approach is ‘full frame’. The ‘window inserts’ type of installation may not be as reliable as removing the entire previous window and installing the new window into the original rough opening. There are a number of reasons for this. First, with the inserts, you are left with two seams that have to be sealed and can potentially leak. These are the seam between the wall and the original outside frame, plus the seam between the original outside frame and the newly inserted window frame. That makes it twice as hard to get a good seal around the window.
The second issue with ‘window inserts’ is the fact that the new window is now smaller than the original one. This means less light and less ventilation. The impact is not overly great. It is generally less than a 10% reduction.
Finally, with ‘window inserts’, it is vital that the old window frames be sound and solid. It is very foolish to install new windows into rotted frames (see the picture). You loose any benefit that the new window can offer when the frame that it is inserted into does not provide solid support or a reliable weather barrier.
So, when you go ‘full frame’ with your window replacement, you get to remove all the old window. This gets rid of any old rot. It also allows you to see into the surrounding wall to see if there is any rot or mould concealed. This lets you do any needed clean-up or repair so that the wall can accept the new window and provide reliable support and performance.
I hear you thinking, if ‘full frame’ window replacement is so much better, then why would anyone go with ‘window inserts’? The short answer is to save time and money. ‘Full frame’ windows have to be custom fabricated to make sure they are sized correctly to properly fit into the rough opening in the wall. This generally costs more. And because they are custom built, they take longer to get. With ‘window inserts’, stock windows are used. These are readily available. They are also mass produced, so they tend to be less costly.
Whenever I do a home inspection, I always check to see what type of window installation has taken place. If I see ‘window inserts’ I take that much extra care to ensure they provide a positive weather seal. I also check the surrounding frame to make sure it is in good condition, and providing reliable support and weather performance.
Ottawa WinterPosted on Thursday, March 27th, 2014 by Nathan Weinstock
What a winter we’ve had this year here in Ottawa! Long, cold, and snowy. No individual weather records set, just lots of cold and snow. This created a special challenge when doing Ottawa home inspections.
Getting around in deep snow was hard. Seeing the roof from above was demanding. But, on the positive side, I knew right away if the heating system was working properly and if it was pumping out enough heat. I could also see right away if the roof was a victim of ice damming. These things are not so easy during a July inspection.
Still, I thought, might as well make the best of the hand we’re dealt. This “special” winter allowed me to enjoy the best of the weather. It was a great season for skating on the Rideau Canal, Ottawa’s great treasure. There were so many days when the ice surface, all 7.8 km of it, was near perfect. So I could get out and relish some great exercise in terrific fresh air. There is nothing more exhilarating than gliding on and on, over hard, crisp ice.
The Ottawa winter festival, Winterlude, was a resounding success this year. The weather cooperated perfectly to allow all the events to run as planned. It was great fun!
So, yes, I’m ready for spring. I’d like to get back into training for my 10k runs. I’m looking forward to tip-toeing through flower beds instead of snow banks during a home inspection. But I will think back on this winter when I am checking the air conditioners during next summer’s heat.
Never Chop A RoofPosted on Friday, February 14th, 2014 by Nathan Weinstock
It has been a tough winter here in Ottawa. The cold weather and heavy snow have made it particularly demanding to do home inspections, especially on the outside. They have also made just living and getting around tough. And the trying conditions created by this winter are especially hard on our houses.
The deep blanket of snow and the arctic temperatures have contributed to the build-up of ice on many of our roofs. I have talked about roof ice damming in the blog entry: “Scary Ottawa Ice” posted on 02/03/2011. Click back to the past blog posts and check it out.
Once you have an ice build-up, it is really difficult to get rid of it. Many things are tried. Generally these have limited success. Sometimes they can cause serious damage, or be down right DANGEROUS.
First thing to know is never climb on a roof in winter. Never place yourself at serious risk. Hire an experienced professional to do the work if you must try something. They should know how to take the right safety measures. Stopping any water leak is not worth breaking your neck for.
Also, never use a torch or any open flame to try and melt the ice. You can easily start a fire and burn your house down. Again, it is not worth it.
Finally, never use an ax, or pick, or any kind of chopper to try and break up the ice (see the picture). This will certainly damage shingles or roof covering. So when the ice finally melts, the water will have an easier time of getting into your house making the leak and the resulting damage that much worse. Then, not only do you have to face repairing the damage the water may have caused, you also have to fix or even replace the roof.
The best offense is a good defense. Do your best to keep ice from forming on your roof in the first place. Increase the levels of insulation and ventilation under your roof to help keep the snow from melting and then re-freezing into ice. And pull the snow off your roof if you can do it safely from the ground with a roof rake.
As a rule, once the ice has formed, you are pretty much stuck with it until the warm temperatures finally arrive (and yes they will come) and nature helps you out.
The Right Humidity LevelPosted on Wednesday, January 8th, 2014 by Nathan Weinstock
We are in the midst of winter here in Ottawa. In fact, this is one of the coldest and snowiest winters we’ve had in a long time. Winter weather provides a special set of home inspection considerations. For instance, what is the right humidity level in the house?
In summer, we are often dealing with high humidity levels on hot muggy days. Winter conditions can be just the opposite, too dry. You can experience things like chapped skin, nose bleeds, and static electrical shocks. The challenge is finding the right level of humidity in the winter.
You might be wondering can there be too much winter humidity? Well, yes. With too much humidity, you get water condensing on cold surfaces, such as on your windows. Even your walls can get wet if the humidity levels get really high. So the target moisture level would be in the range between 30% – 45%.
How do you know that you have the right humidity level? You could invest in a hygrometer (an instrument used for measuring the moisture content in the atmosphere). But we’re not talking about worrying about an exact number. There is a simple trick you can use to tell if there is enough moisture in your inside air. Simply look at your windows.
With the right humidity level, you should have a light mist or a few water droplets at the bottom of your window. (Please see the picture.) With no moisture, your house is too dry. If water is pooling on the window sill, or running down the walls, then the house is too humid. Keep in mind, I am talking about relatively new, energy efficient windows. Older, less efficient windows often get covered in ice and do not provide a reliable reflection of humidity levels.
So there you have it, a simple test that can tell you so much. If you find you have too much humidity, then you need to run some exhaust fans, or even briefly open a window, until you expel some of the moisture. To find out what to do if your house is too dry, take a look at a previous log post:
Furnace Humidifier Gone Bad
Posted on Wednesday, October 5th, 2011
Cast Iron Sneaking UpPosted on Friday, December 6th, 2013 by Nathan Weinstock
The plumbing system in a typical Ottawa home has two parts. There’s the supply piping that brings fresh water in. Then the drain-waste-vent (DWV) piping system, usually referred to simply as the drains, removes the ‘used’ water. During a home inspection, it would be glaringly obvious if there was a serious problem with the supply piping. Water would be spraying all over or pouring into the house.
Problems with drain piping may not be quite so apparent. There could be rust and decay lurking inside the pipes that you would not know about until they fell apart and started to leak. Your household drains can be made of plastic, copper, galvanized steel, cast iron, brass/bronze, and even lead.
Let’s talk about cast iron as an example. It was extensively used up until the 1960’s and presents its own unique set of problems. Iron, as you may know, can oxidize. That means it rusts. This is done in the presence of water and air. Where do you get this combination with a cast iron pipe? The answer, on the inside. So the deterioration, the rusting, happens slowly, silently, and out of sight, inside the pipe.
Cast iron failure generally occurs precipitously (suddenly). The pipe will work fine and reliably for many decades, and then, it will disintegrate right before your eyes. Just a light tap or hit can cause major disintegration or rupture.
Sometimes, if you are lucky and are paying attention, you get some warning, like rusting and staining on the outside (see the picture).
So, if you have drains made of cast iron, and they are over 30 years old, you should pay careful attention to them. Watch them closely so can you catch any deterioration or leak early on. Or better yet, replace them with new plastic piping. This is fairly easy to do and not that costly. That way you don’t have to worry about damaging drain leaks sneaking up on you.
Still RunningPosted on Wednesday, October 16th, 2013 by Nathan Weinstock
I thought I’d take a break from talking about inspection issues and surprises and tell you about my latest Ottawa run, the Alterna Run. This event was staged to raise funds to fight men’s cancers. It was a cool day with the threat of rain. Fortunately, the rain held off until the end of the run.
This was one of the smaller events in Ottawa with a few hundred participants. So it had a bit of a collegial, friendly vibe. That was very nice. And the route, along the Rideau canal, was very attractive, very scenic.
There was the added treat of a pancake breakfast served to the runners at the end. And I had the pleasure of having my flap-jacks handed to me by my lovely wife, Amanda. She was one of the volunteers helping out.
So, with a respectable running time of 0:59:15.5, a delicious breakfast, and the satisfaction of helping a worthy cause, I’d say this was a very successful event for me.