I can probably shed some light on what they mean by "no pad". Tilson will build a small pad to give the home good drainage away from the foundation and to get the site somewhat level. What they don't do is what some call "cut and fill". This is spec'd by some geotech reports that basically will say to remove 3 feet of existing soil and bring in 4 feet of select fill, for example. There is nothing wrong with doing it that way but it is time consuming and less cost effective given that they are't building in a subdivision where there are multiple jobs to split the cost with. In addition to this, if not done correctly you open yourself up to settlement issues when dealing with fill pads. Our firm's view is we want to keep it simple and design a beefy foundation to stand up to the existing soil conditions rather that try to manipulate the soil to go with a lighter foundation design.
Regardless of the construction of the pad or lack there of, we send a drilling rig out and take two borings within the footprint of the home. One will be 30' deep and one to 20' and we take samples at 1' intervals to determine soil type and give foundation recommendations. These recommendations tell us how much concrete, reinforcing, etc. is needed to make the foundation behave on the soil present. The area you describe can have either expansive clay or very sandy soil so there is a possibility of having an ultra heavy foundation with tons of extra concrete or a lighter one depending on soil type. Here are two links if you want to kill some time and get a general idea of the soil of your project. An extreme generalization but as far as foundation performance goes: lots of clay=more expansive=heavier foundation; sandier soils=less expansive and better draining=lighter foundation.
https://websoilsurvey.nrcs.usda.gov/app/WebSoilSurvey.aspx
You can zoom to your area, select the area of interest, and see soil types.
https://www.twdb.texas.gov/groundwater/aquifer/GAT/
You are probably on the Seguin sheet here.
We deal with jobs on occasion where, at some point in the past, the homeowner had a friend who dug a pond or something and gave them the soil to build the "pad". They didn't properly compact the soil, there is no telling what type of soil it is, whether it is free of organics, or if it can properly support the home. The sales person probably mentioned these because they create issues that we have to deal with when designing the foundation. On these we typically have to add piers under the slab to get it to bear on existing soil that is well compacted and has a known bearing capacity.
If you have any specific questions I'd be happy to answer here or I can post my email.
Regardless of the construction of the pad or lack there of, we send a drilling rig out and take two borings within the footprint of the home. One will be 30' deep and one to 20' and we take samples at 1' intervals to determine soil type and give foundation recommendations. These recommendations tell us how much concrete, reinforcing, etc. is needed to make the foundation behave on the soil present. The area you describe can have either expansive clay or very sandy soil so there is a possibility of having an ultra heavy foundation with tons of extra concrete or a lighter one depending on soil type. Here are two links if you want to kill some time and get a general idea of the soil of your project. An extreme generalization but as far as foundation performance goes: lots of clay=more expansive=heavier foundation; sandier soils=less expansive and better draining=lighter foundation.
https://websoilsurvey.nrcs.usda.gov/app/WebSoilSurvey.aspx
You can zoom to your area, select the area of interest, and see soil types.
https://www.twdb.texas.gov/groundwater/aquifer/GAT/
You are probably on the Seguin sheet here.
We deal with jobs on occasion where, at some point in the past, the homeowner had a friend who dug a pond or something and gave them the soil to build the "pad". They didn't properly compact the soil, there is no telling what type of soil it is, whether it is free of organics, or if it can properly support the home. The sales person probably mentioned these because they create issues that we have to deal with when designing the foundation. On these we typically have to add piers under the slab to get it to bear on existing soil that is well compacted and has a known bearing capacity.
If you have any specific questions I'd be happy to answer here or I can post my email.