Lyons Red Sandstone was the traditional sidewalk material in Denver and surrounding communities before the arrival of concrete. Flagstone is a far superior product to concrete, and even today, many of these original Flagstone sidewalks are still performing well.
Even though the stones are still good, many have settled or been moved by trees and the like and now require resetting or adjustment. Others, that are broken need replacing. According to City law, the sidewalks are the responsibility of the homeowners, and they are required to maintain them. For years, the city has not enforced its sidewalk regulations, however, it has been decided that the condition of many sidewalks is a problem and the code regarding them needs to be enforced. This means zone by zone inspection of the sidewalks in the city and many homeowners are being told that they must repair the sidewalks.
The Problem: If your sidewalk has a height difference of more than 3/4″ between any 2 adjacent stones in a single jump than you will be required to relevel that section of sidewalk. Also, if your sidewalk has a section where the grade (slope) of the sidewalk exceeds 5% (1″ of height change in 20″ of distance) that section will need to be releveled.
The City: The city is inspecting all the sidewalks and will send you a letter informing you of any problems it finds in your sidewalks. They will make the “generous” offer of having their contractor fix it. This means that they will replace your historic Flagstone with concrete. While this will solve the problem for a while, it is far from an ideal solution.
Why should you keep Flagstone: Besides the obvious historic nature of the flagstone, there are many other reasons to keep the flagstone or even replace your concrete with Flagstone.
- Value: The shorter lifespan and inferior appearance of concrete will lower your property value. The original flagstones that are still solid today were set directly in the dirt rather than being properly bedded. Flagstone with bedding in sand and compacted crusher fines will create a walkway that will last centuries. As the stone ages and becomes a full part of the environment of your house and yard, it will only increase the value of your property.
- Green: Natural stone is a green building product. Concrete is a very carbon intensive product. Locally sourced natural stone has a far smaller carbon footprint than concrete.
- Flexibility: Trees will always get bigger. When a tree root encounters a slab of flagstone, it lifts the stone, you can simply reset the stone. If that same root encounters a concrete sidewalk the concrete breaks and a whole new slab must be poured.
How to keep your Flagstone: Act promptly. Call a contractor. Not sure who to call? Call us, and we will make a recommendation. The City has stated that you have 45 days to resolve the problems. Lyons Sandstone has, along with others, explained to the city that that is not a viable schedule for stone and they have decided that as long as you are showing “due diligence” and making an effort to fix the problem they will not hold you to the 45 days. You do need to make it clear to them that you are working on the problem.
- A Block Party: By working with your neighbors who are facing the same challenges, and selecting a single contractor and single source, you can save quite a bit of money. Mobilization and delivery cost the same whether a contractor is there to do 3 stones or 300, The larger the project, the more those costs can be dissipated.
- Many stones can be simply lifted, re-bedded and set back in place. Some may require replacement, which is where Lyons Sandstone comes in.
- Select the right contractor: some contractors are much better and faster at this kind of work than others. A Vacuum lift and a bobcat can make the process of achieving a good lift, bedding and setting much faster and easier and therefore less costly.
Improvements: take advantage of this requirement to improve your sidewalk. Traditionally these Flagstones were cut by hand with a chisel or mechanically with a “Snap Cutter”. Both of these are effective, but leave a rough side on the stone that requires a wider joint (.5″ – 1″). Today with modern equipment Lyons Sandstone can, for a modest upcharge, provide sawn sided Flagstones. These Flagstones have a perfectly straight and smooth side and can be set much closer together (1/4″ or less). This can be especially valuable in Commercial areas where ADA concerns are greater but can offer value to every property owner.
Don’t give up your Flagstone. Keep historic Denver historic.
Natural Stone Institute
Rocky Mountain Masonry Institute