Do It Yourself Concrete Wall Insulation


Every now and then we have to insulate the inside of a foundation wall. Concrete walls have zero insulation value, according to the building code. In our cold sector of the country, we have to insulate walls to an R-Value of 21. I recently had just such an occasion, to insulate a concrete foundation wall in a home that we were remodeling in Rye, NH.

You see, this foundation was built as part of an addition, some years ago. It seems that whomever built this addition didn’t pay quite enough attention to the little details. There are water pipes running through this utility area, with no insulation on these concrete walls and no heat source. What do you suppose happened to those water pipes this winter? They sure did freeze, unfortunately.

See how close the water pipes are to the exterior rim band? On the other side of that 2″ thick foam piece that we sealed around the edges of lie below freezing temps.

What did we do about it? Well, we decided to make this utility area of this addition warm. We started by determining what the vulnerabilities are, and then convert them into strengths. The rim band of the floor framing (where floor joists terminate over an exterior wall, in this case foundation wall) is a typical vulnerability. This one’s no different. We decided to use standard 2″ blue foam insulation board and fit it into these spaces between the joists. We then seal around it with the spray foam gun.

The next and only other major vulnerability is the concrete foundation. In this case, the foundation walls are exposed entirely to the elements on the other side, no earth for insulation purposes. So, if these concrete walls essentially have no insulation value, let’s rectify that. I chose to walk a nice balance between frugality and functionality. We wanted to keep the cold out and the heat in, but without spending a fortune. We also want to provide a safe finished product. Leaving most foam board products exposed would be unsafe and a code violation. They will easily ignite. I didn’t want to have to sheetrock or put plywood over the foamboard, so I decided to upgrade to Dow Thermax. You’ll have to research whether this can be left exposed in your municipality, but I chose to go with it here.

We start by applying adhesive to insulation pins. The adhesive is made specifically for this purpose and emits rather potent fumes, so take precautions. After letting the pins cure to the concrete overnight or so, it’s now time to cut and fit the insulation board onto the pins. We air seal the perimeter of each sheet with the fire resistant foam from the foam gun, and we’ve just sealed out the cold. We opted to only go with 2″ foam, which now gives our wall an R-Value of approximately 13. Not quite up to code for new construction, but probably about 500% better than it was. Also, we weren’t required to adhere to building code because we didn’t need a permit for a repair of this nature.



Finally, we decided to maximize heat that was already available, instead of install a new heat source. We cut a nice hole through the plywood that had been used to block in an old foundation window dating from before the addition. On the other side of this plywood window, there is a wall mounted on demand boiler hot water heater. The heat transmitted from the existing mechanical room was ample enough to supply the previously cold, adjacent room.

Eldredge Lumber in York, Maine carries the Thermax insulation for around $60 per 4′ x 8′ sheet, and Ricci Lumber in Portsmouth, NH special ordered in the pins and adhesive. The minimum order was 1,000 insulation pins, and we used a quart of adhesive. The total for these 2 items was under $200. We air sealed the edges of all the panels with a fire retardant spray foam from a can. We used 6 sheets of the foam insulation for the concrete walls, and 2 sheets for the rim band where the floor joists meet the exterior wall. Super simple, you can do it!!!

Timeless Solution to Age Old Problem

Know anybody with wooden gutters? Chances are they enjoy talking about the character and beauty of them, but don’t want the conversation to sway towards the

Rye Beach NH contractor

This was from my initial assessment of the home.

maintenance of them. They do have many checkmarks in the “pros” column for the aesthetic appeal, but each “pro” is also offset but a baneful “con”.

I was referred to these particular homeowners in Rye, NH to replace rotten eave trim and porch trim before having their house painted. Upon arrival I asked the homeowner what his wishes were and what his analysis was, since they have owned the home for 26 years. I then applied this perspective and my professional perspective as I walked the exterior of the house, took measurements and

Home repair Rye NH

This was the typical rotten trim we were asked to estimate. Clearly we were going to have to replicate some ornamental brackets.

pictures, and made notations. I returned to discuss my findings and display pictures with the homeowner. I told him that we could certainly replace all of the rotten trimwork, replicate a couple of the decorative cornice brackets, and tighten things up ahead of a paint job. Unfortunately, I also had to gently disclose that it seemed clear that the wooden gutters were causing the rot all around the home, and it was likely to continue. I asked what his thoughts were about this and he

Wood gutter repair

It can’t be good when my chubby finger can fit into the joint.

remarked, “I’ve resigned myself to the fact that rot is just going to continue to be a problem.” These particular homeowners are very intelligent and do an outstanding job trying to maintain the integrity of the home. I feel as though this response was a result of decades of conditioning by previous contractors stating exactly that. I also had to gently state that I didn’t share this same viewpoint with regards to this specific example, and that after providing a detailed proposal for replacing the rotten wood trim, I would also research to find a winning solution for conquering the age old wooden gutter problem.

By looking at these pictures, you can see that the gutters are placed over the fascia board, but starting to pull away. This creates a wonderful alternative for water seeking to hide. All of the joints in the gutters have separated like Heidi Klum and Seal, no chance of getting back together.

Wood gutter repair Rye, NH

Water definitely should not be allowed behind this gutter.

Compounding the problems greatly, one of my predecessors decided to resolve the issue of gutters pulling away by supporting them with another layer of wood trim applied to the fascia underneath the gutter, and then sealed it together with caulking and paint. While this looked terrific from the ground, it didn’t work out so well from a “water management” perspective. All of the moisture that ran behind the gutter was sealed in with no place to go. Of course it rotted the trimwork, layer by layer. If all this wasn’t bad enough, some of the original downspouts were eliminated and patched over for aesthetic reasons. Fine, except that the gutter still pitched in that direction and now the water would sit there until it evaporated. Another detail requiring attention was where the gutter sections butted into the exterior walls and siding. There was no endcap sealed on to the butt end of the gutter, nothing to protect the wall from this moisture. I showed the homeowner all of these pics and more, so he could see why I felt it deserved attention.

Finding the winning solution wasn’t so easy. I spent 2 full days talking with other building professionals, talking to the local suppliers of gutter and roofing products, in professional chatrooms, and spending countless hours poring through Google search results. The end result: There was no ready made solution. I was going to have to create one. We could have copper manufactured and soldered to be seamless in place, for over $8,000. Or we could use white rubber roofing and lead for ½ the price.

In order for the gutter to hold the water and direct it properly into the downspouts, we had to ensure that the white rubber roofing liner would be tucked all the way up under the roof-line. Then, we had to find a way to seal the rubber roofing to the top edge of

Wood gutter repair

Time to start putting things back together.

the gutter, where it wouldn’t be seen from the ground. By nailing the lead to the gutter, it gave us a nice, clean, smooth, and impermeable surface to bond the rubber roofing to… for all eternity, ahh, ahh, ahh. But, there was one more critical task we were going to ask the lead to perform. We needed to create a “drip edge” on the outside face of the gutter for overflow water to drip off of, rather than submit to it’s surface tension

Wood gutter lining Rye, NH

Installing the rubber membrane under the roof drip edge and sticking to the gutter and the lead at the top edge of the gutter. All edges will need to be sealed with lap sealant engineered for rubber roofing membranes.

and run all the way down the face of the building components. We did this by adding a

Wood gutter liner

The finished product isn’t so glamorous up close, but looks great from the ground.

spacer to the top outer edge of the gutter and then hanging the lead slightly lower than it. We also added 3 new downspouts where the demand required.

I’m 100% certain that Meticulous Remodeling had not just boldly gone where no man has gone before, but proud of our extra effort and craftsmanship, nonetheless.


By John Bradshaw

Wood trim repair Rye Beach, NH

Instead of using solid cedar which would crack and split, we used weatherproof glue to join cedar boards for a more stable product.








Home repair Rye, NH

This is the finish painted product as seen from the ground. You may notice the unpainted lead at the top edge. Also, the bracket on the left is a new one.