What You Need to Know About Stone Foundations

If your home was built before 1915, it may have a stone foundation. As the most common foundation type in historic homes, we often see stone foundations when inspecting homes and older buildings in the Milwaukee region. 

 

Stone foundations do pose unique challenges but do not have to be a dealbreaker when purchasing the historic home of your dreams. With an experienced historic home inspector on your team, you can equip yourself with the knowledge you need to repair and maintain a stone foundation. 

 

At Towne & Country, Scot McLean applies his passion for history to providing expert historic home inspections in Milwaukee and surrounding communities. Scot’s extensive knowledge of regional architecture and the unique characteristics of historic homes makes Towne & Country Building Inspection Milwaukee’s go-to resource for historic home and building inspections. Give us a call to schedule a consultation today. 

 

Stone Foundations 101: What You Need to Know

 

When deciding to purchase a historic home, you may be nervous about sloping floors and crumbling plaster in the basement or around the exterior of the foundation. However, these characteristics do not necessarily mean you will need to pay for a full foundation repair. Settlement and minor shifting are normal for stone foundations, especially in homes older than 100 years. Crumbling plaster is a relatively simple fix if you hire the right expert. As long as the stones of the foundation are generally in the same place the original builder put them, you can expect that they will likely stay there. 

 

Crumbling Mortar & Repointing

 

Most historic homes in the Milwaukee region are coated with a mortar mix that can flake off over time due to moisture and movement issues. When this more solid mixture flakes off the outside of the stones, the more crumbly interior mortar can also start to erode. 

 

As soon as you notice this flaking start to happen, you will want to bring in a specialist to repoint (i.e. repair) the mortar. In almost all cases, you will only need to repoint the area that is experiencing the issue, rather than redoing the whole foundation. As long as you are proactive about repointing when and where it is needed and your foundation otherwise remains solid, you should be good to go. 

 

Protecting Against Basement Moisture

 

One unfortunate feature of stone foundations sealed with mortar is that they likely will not protect against moisture seepage. Wisconsin’s wet and snowy weather causes the soil around any foundation to expand and contract, exerting pressure on the foundation and potentially causing cracks. With a foundation material that is already porous, as with stone foundations, water will have an easier time creeping in. 

 

That’s why it is critical to install and maintain a drainage system around the exterior perimeter of a stone foundation. You will also want to ensure the ground around the foundation and any exterior structures like a patio slope away from the home. Moisture coming off the roof should be carried away from the foundation by a properly functioning and clean gutter system, and be sure your sump pump discharge pipe empties well away from the home. 

 

It’s best to avoid sub-grade drainage systems and interior waterproofing systems in homes with stone foundations as these can cause more problems than they fix. Sub-grade drainage systems actually work well with stone foundations, but require the well-compacted soil around the foundation to be disturbed in the installation process, which can cause the foundation to move and shift. Interior waterproofing systems can cause soil erosion underneath the foundation, which can also cause undesirable movement. 

 

An expert home inspector like the team at Towne & Country can recommend stone foundation experts who can provide you with the information you need to protect your historic home against basement moisture. 

 

Call in the Experts for your Historic Home Inspection

Towne & Country Building Inspection is Milwaukee’s go-to expert resource for historic home inspections. If you are a lover of historic homes and are on the market for your very own piece of history, you will want an expert inspector on your team. Not only do we know what we are talking about, but we bring a passion for Milwaukee’s history and architecture that is unparalleled. Give Towne & Country a call to get started today.