1. Common House Spider

The common house spider is the spider most Pittsburgh homeowners encounter most frequently. These are small brownish tan spiders that build messy irregular cobwebs in corners, windows, basements and garages.

Danger level: None — completely harmless to humans

House spiders are actually beneficial because they catch and eat other insects including mosquitoes, flies and gnats. However their webs are unsightly and accumulate quickly. A heavy house spider presence usually indicates a larger underlying insect problem that is attracting them into your home.

What to do: Remove webs regularly and address the underlying insect population that is attracting them.

2. Cellar Spider (Daddy Long Legs)

Cellar spiders — commonly called daddy long legs — are the long legged delicate spiders you frequently find in basements, crawl spaces, bathrooms and dark corners. They build loose irregular webs and hang upside down in them.

Danger level: None — completely harmless

Despite the popular myth that daddy long legs are the most venomous spiders in the world their fangs are actually too small to penetrate human skin. They are completely harmless and beneficial predators. However their webs accumulate rapidly in basements and crawl spaces and can make your home feel neglected and unkempt.

What to do: Remove webs regularly and seal entry points to reduce population.

3. Wolf Spider

Wolf spiders are large brown hairy spiders that do not build webs — they hunt actively on the ground. They are commonly found in basements, garages and on the ground floor of Pittsburgh homes especially in fall when they come inside seeking warmth.

Danger level: Low — not dangerous but can bite

Wolf spiders look genuinely intimidating and their large size — up to an inch and a half in body length — can be alarming when you encounter one unexpectedly. However they are not dangerous to humans. They can bite if handled or cornered but their venom is not medically significant for most healthy adults. Reactions are typically limited to mild localized pain and swelling.
Wolf spiders are actually excellent predators of other insects including cockroaches and crickets. However their presence inside your home is a sign that other insects are present to attract them.

What to do: Seal foundation gaps and exterior entry points to prevent them entering your home.

4. Jumping Spider

Jumping spiders are small compact spiders with large forward facing eyes that give them an almost endearing appearance. They are active daytime hunters that stalk and jump to catch prey rather than building webs.

Danger level: None — completely harmless

Jumping spiders are commonly found on windows, sunny walls and around window frames in Pittsburgh homes. Their large eyes and curious nature make them one of the more interesting spiders to observe. They are completely harmless to humans and are actually beneficial predators.

What to do: No action needed — they are harmless and beneficial.

5. Yellow Sac Spider

This is where things become more concerning for Pittsburgh homeowners. Yellow sac spiders are small pale yellow or cream colored spiders that build silk tube retreats — small silken sacs — in corners, along ceiling wall junctions, behind furniture and under objects.

Danger level: Moderate — the most common biting spider in Pittsburgh

Yellow sac spiders are the most common spider to bite humans in Western PA — usually when they become trapped against skin while a person is sleeping or getting dressed. Their bite causes a painful burning sensation with localized redness and swelling. While not medically serious in the way a black widow bite is their bites are genuinely unpleasant and can cause significant discomfort for several days.

If you are finding small silken sac retreats in the corners of your rooms or along your ceiling wall junctions you likely have yellow sac spiders.

What to do: Call a professional for treatment — yellow sac spiders are difficult to eliminate without professional pest control.

6. Brown Recluse

We need to be very clear about this species. Genuine brown recluse spiders are extremely rare in Pittsburgh and Western PA. Brown recluses are primarily established in the south and midwest United States and are not a naturally occurring species in Pennsylvania.

Danger level: High IF present — but extremely unlikely in Pittsburgh

However we receive calls about brown recluse sightings regularly and the vast majority turn out to be harmless brown spiders that superficially resemble a brown recluse. The most reliable identifying feature of a brown recluse is the violin shaped marking on its back — but this requires close examination and confident identification.

If you genuinely believe you have brown recluse spiders in your Pittsburgh home call us immediately for a professional identification. Do not attempt to handle or collect the spider yourself.

What to do: Call Spectrum Pest Control for a professional identification — 412-532-1380.

7. Black Widow

Black widows are occasionally found in Pittsburgh and Western PA — and this is one species every homeowner should know how to identify.

Danger level: High — medically significant bite requiring immediate attention

Black widows are recognizable by their shiny jet black body and the distinctive red hourglass marking on the underside of the abdomen. They prefer undisturbed dark areas and are most commonly found in:

Woodpiles and lumber stacks
Garages and sheds
Crawl spaces and basements
Under outdoor furniture and play equipment
Inside rarely used boxes and stored items

Black widow venom is a neurotoxin that can cause severe muscle pain, cramping, nausea, sweating and in rare cases more serious complications. Black widow bites require immediate medical attention.

If you find a black widow in or around your Pittsburgh home do not attempt to handle or treat it yourself. Call Spectrum Pest Control immediately for professional removal.

What to do: Call us immediately at 412-532-1380 — do not handle or disturb.