As busy homeowners, we know you have questions. As expert professionals, we have answers.

Frequently Asked Questions

We’ve all experienced businesses that don’t keep things clear and concise. Here are a few questions we get asked, and the answers that only MDTH can provide. Call us today with your own questions, or request your free quote. We can’t wait to serve you!

What is the cost for exterior home cleaning?

To give you an idea of a basic home wash price we begin at $0.25 per living square foot of the home. There are many variables taken into consideration, including but not limited to:
Scope of work
Size of the project
Type of disturbance we are working to remove
Site access

We prefer to get eyes on every project to adequately assess your needs and give you a formal, firm, quote to assure no one is surprised at the end of the day.

Licensing & Insurance

Believe it or not, in Michigan pressure washing is a regulated industry and there are several licenses and permits required. Any individual operating mobile pressure washing for hire is required to have a wash water discharge permit issued by the Michigan Department of Environment, Great Lakes, and Energy.
Any individual “soft washing” or using cleaners to remove/kill algae, moss, mildew etc. (you may hear the terms SH or sodium hypochlorite) is required to have a Pesticide Business License and a technician onsite must have a Pesticide Applicators License issued by the Michigan Department of Agriculture. We also maintain adequate general liability, workman’s compensation, and commercial automotive insurances to assure your persons, property, and our employees are adequately protected. Copies of our licensing, insurance, and certifications accompany every quote to every customer.

Pressure vs. Power vs. Soft Washing

Pressure washing is using cold water and high pressure (generally 2500 upwards of 5,000 psi) to forcefully remove disturbances. Generally should be used for substrates of high surface strength such as concrete or brick. We do not recommend pressure washing any form of siding especially never on a roof.

Power washing is using hot water and high pressure to forcefully remove disturbance. Power washing is typically used for commercial or industrial applications where grease and oils need to be removed from concrete, masonry, machinery, or equipment. Power washing is also an effective way to remove gum from concrete.

Soft Washing is our recommended method for cleaning of most residential delicate surfaces of numerous different disturbances, including mildew, algae, rust, etc… Soft washing is what we recommend be used on all types of siding, composite decking and roofs. Soft washing is using the proper soaps and cleaners to do the “heavy lifting” so much lower pressure can be used to gently rinse your home clean. This is by far the best method to clean your home and the safest way to assure your biggest investment is protected from damage.

Residents & Pets

Safety is always our highest priority! It is our policy that no individuals or pets are in the work area while cleaning is in progress other than those individuals employed by MDTH Services. We are knowledgeable of all our cleaning products both their proper use and follow all manufacturer safety precautions. Every soap or cleaner we use is adequately diluted and/or neutralized prior to completing your project. We are parents and pet owners ourselves and understand that the safety of your family and pets is of the utmost importance. In order to assure the highest level of safety we request that you abide by our safety policies

Landscaping & Property

We understand that maintaining the beauty of your landscaping is important. We are incredibly mindful of all our equipment and movements through your landscaping during the cleaning process. All hoses will be neatly managed around the project to mitigate any trip hazards. Safety cones will be utilized at any necessary areas to bring extra attention to potential hazards. We are highly skilled in plant and property protection to assure your investments are safe. All necessary protections will be put in place to assure damage to landscaping is mitigated. All soaps and cleaners will be adequately diluted and/or neutralized throughout the cleaning process. Your landscaping will be watered prior to any soaps being applied, directly after soaps are applied, and after soaps are rinsed from the project Our staff will assure that prior to any water being sprayed that your home is adequately protected. Electrical plugs will be completely taped off and any security systems will be covered to avoid any water intrusion. While water intrusion is always a possibility, we do exhaust all protective measures to mitigate the risk.

Soaps & Cleaners

We use a variety of professional soaps and cleaners that are specifically designed for the exact disturbances we are addressing. We have spent many hours researching, testing, and selecting only the highest quality products to provide you with exceptional results. All soaps and cleaners will be adequately diluted and/or neutralized to assure the safety of your family, pets, landscape, and property. For generalized cleaning of organic materials, such as algae and mildew, the primary active ingredient is Sodium Hypochlorite, commonly known as bleach, combined with a surfactant that is specifically designed for exterior cleaning. For inorganic disturbances, such as rust, efflorescence, oxidation, and other inorganic matter we utilize a variety of cleaners, both acidic and caustics, specifically designed to address the exact disturbance. We are happy to provide you with SDS sheets for all cleaners that will be used on your project available upon request.


We use a variety of high-quality, professional equipment to assure you receive the professional results you expect. From high pressure washing necessary to clean strong substrates such as concrete, masonry, and equipment to low pressure “soft washing equipment” safe for delicate surfaces such as siding and roofs, MDTH Services has the specific equipment to assure the results and safety for your project.


In most cases your exceptional results will be the same day, however when it comes to roof washing patience may be necessary. Heavy moss on roofs can take 30-60 days to safely release post cleaning, though you will see same day results that the cleaners are in fact doing their job. We never want to forcefully remove any disturbances from your roof, but rather allow the soaps to do the work. Our knowledge of cleaning processes and soaps coupled with our investment in the highest quality equipment allows us to be incredibly efficient and offer you the highest quality clean available.

What is oxidation?

Oxidation is a normal degradation of surfaces due to oxygen and heat exposure.

Typically oxidation is most noticeable on siding as a “chalky” substance.  When we rub a finger over the surface the chalky substance will be visible on our finger and a noticeable sheen variation will be seen on the siding.

Oxidation removal requires an additional application of a separate cleaner from the basic home wash and requires physically agitating and brushing the oxidation in order to remove it.

The risk of oxidation removal is that it can expose underlying thermal bridging.  Thermal bridging is noticeable by a color variation in the siding due to heat transfer from building materials behind the siding such as nails or wall studs.  Thermal bridging is not always a problem and sometimes cannot be noticed until the oxidation is removed.  There is no remedy for siding that has deteriorated from thermal bridging.

Call For a Quote:

(248) 469-0701

Roof Cleaning FAQs

What is growing on my roof?

The short answer is Gloeocapsa Magma which is a cyanobacteria that closely resembles an algae. The long answer is that your roof may have an entire bio-mass growing up there! The Gloeocapsa Magma creates a moist bed where other growth can attach such as lichens, ferns, mildews and more! You’ll notice this growth more prevalently on the north side of your roof, but in time it can spread over the whole roof system. 

Should my roof be cleaned?

The biological growth that is living on your roof is holding moisture up against the roofing material. It’s also giving a “toe-hold” for other organisms to take root. Besides being an ugly cosmetic blemish, this growth may be diminishing the lifespan of your roof. Additionally, roofs have a certain reflective quality and the growth up there could be making your electric bills higher than they should be! If leaves and debris are packing up in the valleys of the roof and laying across the shingles, this rotting vegetation can also be holding moisture and exacerbating very detrimental conditions for the longevity of that covering. However, there are some roofs that are too dangerous for us to clean or have a reached the end of their lifespan. Spending money on a cleaning process just doesn’t make financial sense in some cases, and your MDTH Services representative will advise you of our opinion in these cases.


If you have a sprinkler system, we strongly recommend heavily watering the plants the day before your scheduled appointment as well as the next day afterwards.


As we are killing “living organisms” including algae mildew, lichen, ferns, etc., we cannot warranty our work for a definitive period. Precipitation, humidity, and temperature impact this biomass and are forces out of our control. On average, most of our customers will not see substantial regrowth or re-staining for 3-4 years.


Roof to be cleaned per ARMA (Asphalt Roofing Manufacturers Association), GAF, and ELK standards. Your roof will be treated with a custom blended sodium hypochlorite (bleach) solution and industry specific surfactants. Our final step in your roof cleaning process will be to apply a neutralizer (Agent Halt) to your roof. This final process will help to neutralize any chemical residue from the cleaning process.

After The Cleaning

You may notice a slight brown hazing after your cleaning, this is completely normal. Some dead algae may remain and will naturally be removed by rains & wind. If after TWO substantial rains you notice remaining staining, we will come back to retreat problems areas on your roof within thirty days of the initial cleaning at no additional cost.

Plants & Landscaping

MDTH Services will make every effort to protect your landscape. You can assist us by moving potted plants out of the immediate area we will be cleaning. If you have plants you are concerned about, DO NOT COVER THEM! Heavy plastics can cause more harm to plants than our roof cleaning mixture. If you have concerns, please address them with MDTH Services and we can cover your greenery with TYVEK or a similar breathable fabric. You may notice browning on a few leaves here and there, this is normal and does not mean your plant is dead or dying. Dry, damaged, and weak plants may have a more severe reaction to a roof cleaning. We will make every effort to prevent landscape damage, but we are killing a “plant” that is living on your roof, and mitigating the risk of harming the plants living in your yard!