Installing Bluestone Over Existing Concrete Patio

by Jerry
(Elk Grove Village, Il, USA)

I have an existing (13 year old) concrete patio.

Can I put bluestone right on top, by adhering the bluestone with mortar, of the existing concrete?

What are the problems associated with this method?

Thank you.

ANSWER

Hi Jerry,
You can install bluestone over an existing concrete patio if the concrete is in good condition. It can't have any settling or cracks.

If this is your situation, I don't see any problems doing this as far as construction goes.
You will, however, be raising the height, so make sure the new patio elevation works with any doorways, steps, siding, etc.

If the patio joins any lawn or planted areas, it will also be higher. You will see the new bluestone and mortared edges, so you may want to raise the grade slightly or do something else to camouflage this.

Regards,
Susan

Paving Joints | Sand Laid Patio With Bluestone

Here's a question about paving joints for a bluestone patio.

We are creating a sand-laid bluestone patio. The stones are 24 inch squares and we want to have them in a grid pattern with 3 inches between the stones for a grid effect. What should be put in between the stones (what type of sand) for a durable lock? The information we have is that polymeric sand is not useful for gaps this large.

ANSWER
This could be an interesting design. However, with such wide joints, I don't believe that polymeric sand or even regular sand would be a good filler. You mentioned a "durable lock", but these won't look good or be easy to maintain. Concrete would be a strong material, but again, I wouldn't like the look of mortared joints with bluestone.

So it seems there are two solutions.

1. Use another material for the joints. This could be lawn, groundcover, or pebbles. Any of these would look nice. If the bluestone is laid properly, they should stay in place even with these options.

There are ground covers called "Steppables". Many will take considerably hard traffic and are hardy. Lawn will be neat, but you have to mow it. There are many pretty pebbles...a small river rock or even a nicely colored crushed stone come to mind.

2. Reduce the size of the paving joints considerably. I would go with about 1/2". You can then use the polymeric sand. You will still see the 24" bluestone square pattern too.

I hope this was helpful. Let me know if you have further questions or comments.

Susan

Bluestone Stair Treads

by JOHN
(ITHACA, NY)

I would like to buy 5 pieces of bluestone stair treads - 2.5 inches thick, 70 inches wide......4 pieces at 16 inch depth and 1 piece at 18 inch depth. Are they available and if so, what would be the total approximate weight and cost? Thank you.

Answer
Hi John,
These would be custom cut and I don't see any reason why it can't be done. I once used bluestone as solid treads which were ten feet wide.

I will check this out and get back to you with what information I can.

Thanks,
Susan

Bluestone Patio layout & ordering

I am in Alaska and want to install a bluestone patio(needs to be ordered & shipped).

It will be dry laid regular dimensional stone with a variety of available sizes (example: 2'x 3's, 1.5'x 2' etc, I'm not sure just what sizes are available) The total patio area is approx 600 sq ft and irregularly shaped with some curves, some angles.

Is there a formula to determine what I need to order and also layout in a random pattern?

ANSWER

Typically the bluestone you are referring to comes in an assortment of sizes. Some suppliers offer diagrams of layouts that you can follow.
I think you are referring to this look:
Bluestone Patios

I came across this site which you might find helpful.
http://www.pennsylvaniabluestone.com/johnson/patterns/

Susan

Bluestone or Granite

by Victor
(New York)

I am in the process of re-doing my front stoop, which is currently made of concrete. Are there any advantage or disadvantages between bluestone and granite?

ANSWER

Hi Victor,
I'm not familiar with using granite outdoors. However, you can use travertine, which is beautiful.
You can take a look at my page on
Travertine Pavers. You can also use travertine tile which is typically set in mortar. Either are very strong and will hold up well.

Bluestone can be set in mortar or dry laid, even for a front porch. It is used a lot and is a great stone. No negatives I can think of.

As far as which one to use, it depends on what is on your house. Bluestone is extremely versatile and looks good with many styles. I find travertine to be a bit more formal? What is the material on your home?

Susan

Dry Laid Bluestone | Mortared Blue Stone or Pavers

by Rob

Dry Laid or Mortared Bluestone - Or Pavers

I need some advice as to whether I should go with dry laid bluestone, mortared blue stone or use pavers that resemble this stone.

We are replacing a raised wood deck with a raised masonry patio. It will be approximately 24-28" off the ground so we can walk out of the house without stepping down. It will have a seating wall about 22" above the patio floor surface. We'll have 2 stairs (probably with 3 steps each). The overall dimensions are approx. 20x30. Perimeter 16" wall (with footers) will be brick to match our home.

We live in Williamsburg, VA and do have shrink/swell soil in our area. I like bluestone with mortar (that's what the Williamsburg Inn in Colonial Williamsburg has and it looks great albeit with some stress cracks). I do realize there is the possibility of cracking even with a concrete slab underneath the stone.

Our landscape contractor prefers using a dry installation Bluestone or concrete pavers (HP Henry Tennyson Bluestone)with polymeric sand for the joints. Another well respected general contractor who builds high end homes suggests going the mortar route especially for a raised patio. I've seen the bluestone laid dry with polymeric sand at a neighbor's home and noticed some of bluestones are raised (after two years). The raised edges are sharp & could cause someone to trip.

I'm leaning toward true bluestone with mortar. However, I may still go with concrete bluestone with the polymeric sand (the EP Henry Tennyson bluestone paver edges don't seem quite as sharp as real bluestone).

I'd like to be able to walk barefoot on the deck/patio and don't want to worry about raised edges. Mortar cracks, dry laid seems to heave up. Any thoughts?

Many Thanks,


REPLY

Hi Rob,
Theoretically, mortared bluestone should not crack if installed properly. However, that's not to say that it won't, and if it does, you end up with a mess. Once there are joints that have cracks, it's difficult to repair them aesthetically. From any repair job I have seen, you can always see where it's been re-mortared.

This is why I prefer the dry laid method. I don't know why your neighbor's bluestone has raised areas. This should not happen if the bluestone is installed properly. You might like to take a look at my
page Paver Installation. Although it is for pavers, it is the same or similar for bluestone. Of course you do not need an edge restraint and you can use the polymeric sand for the
bluestone joints. Also, the nice thing about dry laying bluestone is that if for some reason anything does happen, they are so easy to re-lay.


The ground beneath the stone base should be undisturbed soil. If it has been disturbed, such as if filled, it needs to be tamped down with a machine in layers. This is important.

I love the look of natural stone and I doubt any paver can compare. Take a look at the bluestone color "full range" in some of the pictures on this page.
Patio Designs

I don't think you will get this type of look with bluestone pavers (which are man made like regular pavers). Installers like them because they are
easy to lay...they are very uniform in shape. Bluestone should be high quality so that the edges are even. If they are not, they might need to be cut on site to make them "square" so that the joints look straight
and professional.

Cost-wise, you'll spend more using natural bluestone but save money by using the dry laid method. If you were my client, I would advise you to go this way and I would also choose this material and method for my own
project.

If you need further help or have more questions, just let me know. I'd be happy to help.